---
title: "Packing deficits by congruence, and an exact certificate for a transport exponent"
subtitle: "Four rounds of a Collatz programme, each step decided in integers or rationals: $1/6 \\to 1/9 \\to 4/45 \\to 1373/25856$"
author:
  - "Aletheia — the programme's documents and rounds; model: ChatGPT, GPT series"
  - "Neo.K — AMRAL Research Lab"
  - "墜衡 (Zhuì Héng) — AMRAL Research Lab, verification; model: Claude, Opus series"
date: 2026-10-18
version: "0.1"
standard: "1"
headline_problem: "Collatz conjecture"
evidence:
  branch: agent/collatz-verification-zhuiheng
  commit: "a2c25aa757c0704bc110458684ef3d459cb3d9e0"
  dir: collatz-verification-zhuiheng
  sources: "data/gate-logs/src54-*.json, data/gate-logs/src55-*.json, data/gate-logs/src57-*.json, data/gate-logs/src58-*.json, data/paper-figures.json, data/gate-logs/suite-totals.json, data/results.v1.json"
abstract: |
  The Collatz conjecture is open, and nothing here bears on it directly. This paper concerns one
  quantity a Collatz programme uses to control a hypothetical divergent orbit: along a segment of
  the accelerated orbit that begins at a value $y$ and ends where the orbit's slack first drops,
  the endpoint is $z = 2^{-D}\,\Pi$ times $y$, with $D > 0$ and a multiplicative correction
  $\Pi = \prod (1 + 1/(3Y_j))$ over the segment's states. The endpoint can lie above $y$ only if
  $\Pi$ is large, and four consecutive rounds of the programme bound $\Pi$ by envelopes growing
  like a power of the segment's length $L$.

  The exponent falls from $1/6$ to $1/9$, to $4/45$, to $1373/25856 \approx 0.0531$, and every step
  is decided in integers or rationals. The second step is one congruence: $3n + 1 \equiv 1
  \pmod 3$, so no accelerated image is divisible by three, and the states pack at spacing three
  rather than two. The third is an exact identity that telescopes. The fourth is not an estimate at
  all but the value of a finite dual certificate, which we print in full; a reader can verify it
  with no computation of ours. We separate the premises carefully: the first two envelopes hold on
  every such segment, and were tested on tens of thousands of them; the last two are proved under
  the premise $z > y$, which describes the hypothetical object and which no real segment we built
  satisfies, so on real orbits they are consistent but untested. We give every proof the paper
  relies on, record what the programme's own records got wrong, and report how the instruments
  were made to fail.
keywords: [Collatz conjecture, Syracuse map, harmonic packing, dual certificate, verification]
---

> **Status of this document.** Preprint, version 0.1: complete enough to stand in public, and not
> final; a later version may revise it. Not prepared for journal submission. Section 10 records who
> did which part, including the parts this line did not do.

# 0. What is claimed, and what is not

Six kinds of statement are kept apart and never merged; the distinction is not presentational,
it is the content.

| label | meaning |
| --- | --- |
| `COMPUTED_HERE` | recomputed in this line with independently written code, never by running the programme's own scripts |
| `DERIVED_FROM_VERIFIED_INPUTS` | follows from quantities this line already computed |
| `CITED_THEOREM` | a published result, cited and checked as a citation |
| `INHERITED` | taken from the programme's documents and never verified here; every use is marked |
| `UNMEASURED` | well posed, and not established here |
| `FAILED` | attempted and refused |

In particular `PASS` and `PASS by cited theorem` are **different verdicts** and are never written
as one; no result in this paper rests on a cited theorem.

**Not claimed anywhere in this paper:** the Collatz conjecture; that a divergent orbit exists or
does not; that any of the four exponents is optimal; that the transport exponents $\alpha_h$ tend
to zero as the modulus grows; that the conditional envelopes of §§6–7 were tested on a real
orbit — their premise is met by none; and any exponent that passes through the programme's
Diophantine input $\rho_\star = 4.1164$. The rounds also derive root-source and dense-overlap
exponents from that input; the programme later withdrew it, and those exponents are left out of
this paper entirely.

**Inherited:** nothing. Every statement below is either proved in full in the text or computed
here, and every universal statement is also checked pointwise on real orbits wherever its premise
is met. The four rounds' statements are the programme's; the proofs written out here are given so
that the paper can be read, and checked, without the programme's documents.

| round | second-layer record | what it adds | exponent of the envelope |
| --- | --- | --- | --- |
| A-U.2d.8 | RUN-036 | the consecutive-odd envelope, and its exact Gamma form | $1/6$ |
| A-U.2d.9 | RUN-037 | no image divisible by three; a span theorem | $1/9$ |
| A-U.2d.10 | RUN-038 | an exact reciprocal-flow balance; a mod-9 span theorem | $4/45$, conditional |
| A-U.2d.11 | RUN-039 | a residue transport identity and a dual certificate | $1373/25856$, conditional |

# 1. The setting

For odd $n$ let $q(n) = v_2(3n+1)$ and $\mathrm{Syr}(n) = (3n+1)/2^{q(n)}$, the accelerated
(Syracuse) map. An orbit is $Y_0 = n$, $Y_{j+1} = \mathrm{Syr}(Y_j)$, with valuations
$q_j = q(Y_j)$ and cumulative valuation $K_u = q_0 + \dots + q_{u-1}$. Write $\beta = \log_2 3$ and
call $\delta_u = u\beta - K_u$ the orbit's **slack** at step $u$. Since
$Y_{j+1} = (3Y_j/2^{q_j})(1 + 1/(3Y_j))$,
$$\frac{Y_u}{Y_s} = 2^{\delta_u - \delta_s} \prod_{s \le j < u} \Bigl(1 + \frac{1}{3Y_j}\Bigr).$$

The **first crossing** of a step $s$ is $e(s) = \min\{u > s : \delta_u < \delta_s\}$, the first
time the slack falls below its value at $s$. A first-crossing **segment** runs from source
$y = Y_s$ to endpoint $z = Y_{e(s)}$; it has length $L = e(s) - s$, states $Y_s, \dots, Y_{e(s)-1}$,
total valuation $Q = K_{e(s)} - K_s$, and slack drop $D = Q - L\beta > 0$. With
$$\Pi = \prod_{s \le j < e(s)} \Bigl(1 + \frac{1}{3Y_j}\Bigr), \qquad \frac{z}{y} = \frac{3^L}{2^Q}\,\Pi = 2^{-D}\,\Pi .$$
The slack has dropped, so $z$ can still exceed $y$ only if $\Pi > 2^D$. The programme's route
controls $\Pi$, and every round below bounds it by an envelope $E(y,L)$ that grows like a power
of $L/y$; the exponent is what the rounds improve. A source is **post-entry** if $s \ge 1$, so that
$y$ is itself an image of the map; the **low-source** regime is $7 \le y \le L$, where the rounds
state their uniform constants.

Two facts about every segment follow from the slack. For $s < u < e(s)$ we have
$\delta_u > \delta_s$ (strictly, since $\beta$ is irrational), so the display above gives
$Y_u > Y_s$: **the source is the segment's minimum.** Its states are distinct unless the orbit
closes a cycle inside the segment; every segment built here has distinct states, and the gates
measure that rather than assume it. And a proper prefix of $m < L$ states is
**subcritical**, $q_s + \dots + q_{s+m-1} < \beta m$, which is the integer statement $2^Q < 3^m$
— that is what it means for the slack not yet to have dropped.

# 2. Three kinds of premise

Every theorem in these rounds is a statement about segments, and its premise decides what a test
on real orbits can show. The second-layer gates measured each premise separately, printed its
denominator, and applied a theorem only where its premise held. Three kinds turned up.

**Met by every segment, by construction.** That the source is the minimum and the states distinct
(§1) held on all 32207 segments of the first round's sweep and all 23689 of the second's, with no
segment failing either. Subcriticality held on all 9517 proper prefixes the second round examined
and all 27345 the third did. Theorems with these premises were genuinely tested.

**Met by no real segment.** The premise $z > y$ — the endpoint above the source, although the slack
has dropped — is the defining property of the programme's hypothetical object, a segment of an orbit
that never comes down. No real first-crossing segment we built satisfies it: none of 68311 in the
third round's sweep and none of 38101 in the fourth's. The depth caps of the first two rounds need
its analogue for nested chains of segments, $z_1 > y_r$, the outermost endpoint above the innermost
source; it was met by none of 24010 chains and none of 15832. A theorem with such a premise
applied to real orbits is applied to nothing.

**Not a premise at all.** The identities of §§3, 6 and 7 hold on every segment unconditionally.

The middle kind is the one that is easy to get wrong, because "zero violations" and "nothing
tested" produce identical logs. Applied without its premise, the first round's depth cap flagged
thousands of chains as violating a theorem that holds; the honest number is that it was applied to
none. So each gate
also carries a planted defect that deletes its premise gate and must turn the run red — which is
what shows the gate is load-bearing rather than merely exclusive. At the fourth round the same
defect produced no violation at all: the certified bound has so much slack on real segments that its
conclusion survives losing its hypothesis. That is a fact about the bound, stated rather than
engineered around, and the defect was made decisive by also tightening the bound's constant.

# 3. The consecutive-odd envelope, and a Gamma form that needs no Gamma

**Proposition 3.1 (first round).** For every segment with distinct states,
$$\Pi \le E_{\mathrm{odd}}(y,L) := \prod_{k=0}^{L-1}\Bigl(1 + \frac{1}{3(y+2k)}\Bigr).$$

*Proof.* The states are distinct odd integers at least $y$ (§1), so the $k$-th smallest is at
least $y + 2k$, and $1 + 1/(3x)$ is decreasing. $\square$

It held on all 32207 segments of the sweep, built from 1249 orbits, with segments up to $L = 51$
and sources up to 425645; no sorted state fell below $y + 2k$. Each factor is
$(3y + 6k + 1)/(3y + 6k) = (y/2 + k + 1/6)/(y/2 + k)$, so
$$E_{\mathrm{odd}}(y,L) = \frac{(y/2 + 1/6)_L}{(y/2)_L} = \frac{\Gamma(L + y/2 + 1/6)\,\Gamma(y/2)}{\Gamma(y/2 + 1/6)\,\Gamma(L + y/2)},$$
a Pochhammer ratio, which grows like $L^{1/6}$ for fixed $y$. The round states this Gamma form as a
theorem and its checker verifies it numerically, reporting a worst error of $3.1 \times 10^{-10}$.
There is nothing to verify numerically: at integer $L$ the functional equation turns the Gamma
quotient into the product it was built from, and the two sides are one rational number. Checked as
rationals, the disagreement is zero on every segment and on all 56 designed pairs up to $L = 400$.
An independent numeric check with the library log-gamma function agreed too, but only after its
tolerance was set by the cancellation it actually suffers: $\ln E_{\mathrm{odd}}$ is a difference of
four large log-gammas that nearly cancel, and a relative-error test under that much cancellation had
reported twelve correct pairs as failures.

# 4. No image is divisible by three

The first round listed as open that a real orbit should beat the consecutive-odd envelope strictly,
with no quantitative statement available. The second round closes it in one line.

**Proposition 4.1.** For odd $n$, $\mathrm{Syr}(n)$ is coprime to 6. Hence every post-entry state
is $1$ or $5 \pmod 6$.

*Proof.* $3n + 1 \equiv 1 \pmod 3$, and dividing by a power of two introduces no factor of three;
the image is odd by construction. $\square$

**Corollary 4.2.** A post-entry source with $L \ge 2$ is $7$ or $11 \pmod{12}$.

*Proof.* If $q_s \ge 2$ then $\delta_{s+1} = \delta_s + \beta - q_s < \delta_s$ and the segment ends
after one step; so $L \ge 2$ forces $q_s = 1$, which on odd integers is $y \equiv 3 \pmod 4$.
Combine with Proposition 4.1. $\square$

Checked directly: of 20000 odd integers mapped, no image was divisible by three; of 24688 post-entry
states, none lay outside $\{1, 5\} \pmod 6$; of 11914 post-entry sources with $L \ge 2$, none lay
outside $\{7, 11\} \pmod{12}$. The premise $L \ge 2$ is load-bearing: every one of the 11775 sources
with $L = 1$ lies outside that pair, as the proof says it must, and a first version of the check
that forgot the premise reported all 11775 as violations of a corollary that holds.

So the states are packed into the integers coprime to 6 — mean spacing three, not two. Let
$a_0(y) < a_1(y) < \cdots$ be the integers at least $y$ coprime to 6; for post-entry $y$,
$a_{2m} = y + 6m$ and $a_{2m+1} = y + 6m + c$ with $c = 4$ if $y \equiv 1$ and $c = 2$ if
$y \equiv 5 \pmod 6$.

**Proposition 4.3.** For every segment with distinct states and a post-entry source,
$\Pi \le E_6(y,L) := \prod_{k<L}(1 + 1/(3a_k(y)))$, and $E_6(y,L) = \Theta_y(L^{1/9})$.

*Proof.* As for Proposition 3.1, with the $k$-th smallest state at least $a_k(y)$. Splitting the
product by the parity of $k$ gives two Pochhammer ratios $(b + \tfrac1{18})_n/(b)_n$ with
$b = y/6$ or $(y + c)/6$ and $n \approx L/2$, each growing like $n^{1/18}$; whence the exponent
$\tfrac19$. $\square$

It held on all 23689 segments; the two-progression Gamma form agreed with the product exactly, on
every segment and on all 42 designed pairs. The deficit against the odd envelope is a power,
$E_6/E_{\mathrm{odd}} = \Theta(L^{-1/18})$. Table 1 shows the finite-$L$ exponents
$\ln E/\ln L$ moving toward their limits; these are trends, not the theorem.

| $y$ | $L$ | $E_{\mathrm{odd}}$, toward $1/6$ | $E_6$, toward $1/9$ | $E_{\mathrm{RF}}$, toward $4/45$ |
| --- | --- | --- | --- | --- |
| 7 | 200 | 0.13160 | 0.09645 | 0.12640 |
| 7 | 12800 | 0.14675 | 0.10278 | 0.10986 |
| 11 | 200 | 0.11626 | 0.08777 | 0.10537 |
| 11 | 12800 | 0.13799 | 0.09786 | 0.09805 |

Table 1: $\ln E / \ln L$ for the three envelopes ($E_{\mathrm{RF}}$ is defined in §6). At every
length shown the third envelope is still above the second; its gain is asymptotic.

The same round's depth cap for nested chains needs $z_1 > y_r$ and was applied to none of its
15832 chains. Its combinatorial half does not need orbits and was enumerated: over 499149 sets of
$\{7, 11\} \pmod{12}$ anchors at depths 2 to 6, no span fell below the proof's allowance
$6(r-1) - 2$, and the phase rule that closes the remaining gap held on every tight set.

# 5. Two span theorems whose premise every prefix meets

Both rounds that follow also prove a statement about the **span** $W$ of a proper prefix — the
difference between its largest and smallest state, plus one — whose only premise is
subcriticality, and so is met by every prefix of every segment. Both proofs are short.

**Lemma 5.1.** On odd integers, $q(n) = k$ exactly when $n$ lies in one residue class modulo
$2^{k+1}$, namely $n \equiv 3^{-1}(2^k - 1)$. Among $W$ consecutive integers, at most
$W/(3 \cdot 2^k) + 2$ are coprime to 3 and lie in that class.

*Proof.* $v_2(3n+1) = k$ iff $3n + 1 \equiv 2^k \pmod{2^{k+1}}$. Excluding multiples of three leaves
two classes modulo $3 \cdot 2^{k+1}$, and each meets $W$ consecutive integers at most
$W/(3 \cdot 2^{k+1}) + 1$ times. $\square$

**Proposition 5.2 (second round).** A subcritical prefix of $m$ distinct post-entry states with
span $W$ satisfies $W > \tfrac{24}{17}\bigl((4 - \beta)m - 12\bigr)$.

*Proof.* Let $N_k$ count the prefix's states with $q = k$. Each state contributes at least
$\min(q, 4)$, so $\sum q \ge 4m - 3N_1 - 2N_2 - N_3$, and by Lemma 5.1
$3N_1 + 2N_2 + N_3 \le 3(\tfrac{W}{6} + 2) + 2(\tfrac{W}{12} + 2) + (\tfrac{W}{24} + 2)
= \tfrac{17}{24}W + 12$. Subcriticality gives $\beta m > \sum q \ge 4m - \tfrac{17}{24}W - 12$. $\square$

The coefficient $17/24$ is where the sieve does its work: without the factor three in Lemma 5.1
every class would be half again as dense, and so would the coefficient. The statement held on all 9517 subcritical prefixes, up to $m = 50$;
on every enumerated window the per-class count even met the tighter bound $W/(3 \cdot 2^k) + 1$.

The third round adds a cost read modulo 9. If $Y_{j+1} = t$ is the image of $Y_j$, then
$2^{q_j} t = 3Y_j + 1 \equiv 4$ or $7 \pmod 9$, since $Y_j$ is coprime to 3; as 2 has order 6
modulo 9, the class of $t$ fixes a least admissible valuation, its **cost**: $1, 2, 2, 3, 4, 1$ for
$t \equiv 2, 1, 4, 5, 7, 8 \pmod 9$ in turn — that is, cost one for $t \equiv 2, 8$, cost two for
$t \equiv 1, 4$. The six entries were rederived from the congruence, not transcribed; no edge of
68311 fell below its cost, and no image fell outside $\{4, 7\}$ after multiplying back.

**Proposition 5.3 (third round).** If the $m$ images of a subcritical prefix are distinct with span
$W$, then $W > 3(3 - \beta)m - 18$.

*Proof.* Odd integers in two classes modulo 9 are two classes modulo 18, at most $W/9 + 2$ of them
among $W$ consecutive integers. So $\sum q \ge 3m - 2(\tfrac{W}{9} + 2) - (\tfrac{W}{9} + 2)
= 3m - \tfrac{W}{3} - 6$, and subcriticality gives $\beta m > 3m - W/3 - 6$. $\square$

The valuation floor and the span bound held on all 27345 subcritical prefixes. Neither span
theorem is promoted to an exponent for $\Pi$: a span controls the diameter of the realized states,
not where their reciprocal mass sits, and the rounds forbid the promotion in so many words.

# 6. The value-order bridge, and an exponent of $4/45$

The step from a diameter to a product needs value-order information, and the third round finds it
in the edge equation itself.

**Proposition 6.1 (identity).** For every edge,
$$\frac{1}{Y_j} - \frac{1}{Y_{j+1}} = \frac{3 - 2^{q_j}}{3Y_j} + \frac{1}{3Y_jY_{j+1}},$$
and summed over a segment,
$\sum_j (2^{q_j} - 3)/Y_j = -3/y + 3/z + C$ with $C = \sum_j 1/(Y_jY_{j+1})$.

*Proof.* Multiply by $3Y_jY_{j+1}$ and use $2^{q_j}Y_{j+1} = 3Y_j + 1$; then sum, and the left side
telescopes. $\square$

It held exactly on all 70810 edges of 2499 orbits and on all 68311 segments. The identity couples
each edge's valuation to its source's reciprocal weight. Write $S_k$ for the reciprocal mass
$\sum 1/Y_j$ over the states with $q_j = k$, and $S$ for the total. The left side is
$-S_1 + S_2 + 5S_3 + 13\,S_4 + \cdots$, so **when $z > y$** it is less than $C$, and
$$S_2 + 5\textstyle\sum_{k \ge 3} S_k < S_1 + C .$$
Expensive valuations must be paid for out of the cheap class $q = 1$. That this balance is
equivalent to $z > y$ is algebra, and it held on all 68311 segments; the balance itself was applied
to none, because none has $z > y$.

**Proposition 6.2 (third round).** For a segment with distinct states, $z > y$ and a post-entry
source $y \ge 7$,
$$S < \tfrac15\ln\Bigl(1 + \tfrac{6L}{y}\Bigr) + \tfrac1{15}\ln\Bigl(1 + \tfrac{12\,L}{y}\Bigr) + \frac{289}{70\,y},
\qquad \Pi < E_{\mathrm{RF}}(y,L) := e^{289/(210\,y)}\Bigl(1 + \tfrac{6L}{y}\Bigr)^{1/15}\Bigl(1 + \tfrac{12\,L}{y}\Bigr)^{1/45}.$$

*Proof.* States with $q = 1$ are $7$ or $11 \pmod{12}$, those with $q = 2$ are $1$ or
$17 \pmod{24}$ (Lemma 5.1 with the sieve). At most $L$ distinct members of one progression of step
$d$, all at least $y$, have reciprocal mass at most $1/y + d^{-1}\ln(1 + dL/y)$; splitting between
two progressions and using concavity gives $S_1 \le 2/y + \tfrac16\ln(1 + 6L/y)$ and
$S_2 \le 2/y + \tfrac1{12}\ln(1 + 12\,L/y)$. With $z > y$ the endpoint is at least $y$ too, so the
$L + 1$ states are distinct odd integers at least $y$, and $1/(ab) \le (a^{-2} + b^{-2})/2$ gives
$C \le \sum_{n \ge y,\ n\ \mathrm{odd}} n^{-2} \le 1/y^2 + 1/(2y) \le 9/(14\,y)$. The
balance gives $\sum_{k\ge3} S_k < (S_1 + C - S_2)/5$, hence $S < \tfrac65 S_1 + \tfrac45 S_2 + \tfrac15 C$;
substitute, and note $\tfrac65 \cdot 2 + \tfrac45 \cdot 2 + \tfrac15 \cdot \tfrac{9}{14} = \tfrac{289}{70}$.
Finally $\ln \Pi \le S/3$. $\square$

So the exponent is $\tfrac1{15} + \tfrac1{45} = \tfrac4{45}$, a gain of $1/45$ over $1/9$; in the
low-source regime, $\Pi < C_{10}(L/y)^{4/45}$ with $C_{10} = e^{289/1470}\,7^{1/15}\,13^{1/45}$.

The two capacity bounds need nothing beyond §1's structure and held on all 68311 segments — 33939 of which have no
$q = 1$ edge at all. The total-mass bound and the product envelope are conditional, and we record a
correction to the second layer's account of this round here: its record grouped the total-mass bound
with the unconditional capacities, but the proof above passes through the balance and through the
cross-term bound, and both need $z > y$. Evaluated on the real segments anyway, the total-mass bound
was never exceeded on any of the 68311, and the uniform form never on any of the 241 low-source
segments. That is consistent with the proposition and is not a test of it.

The round also limits itself. It builds a relaxation that satisfies every static one-point
valuation constraint yet keeps the exponent $1/9$, showing that the gain cannot come from valuation
counts alone. Its two closed forms, a density $D(t) = 1/(3(2 - t))$ and an average valuation tending
to $2/(2 - t)$, eliminate to a relation between the round's own reported figures,
$\overline{q} \to 6|S_X|/X$. At the three reported sizes $X = 30000$, $100000$ and $300000$ — counts
7137, 23802 and 71423 — the gap is $2.01 \times 10^{-3}$, $7.19 \times 10^{-4}$ and
$1.81 \times 10^{-4}$, shrinking as the $o(X)$ in $|S_X| = D(t)X + o(X)$ predicts, and the
recovered $t$ converges to $0.5999$. A first attempt at this check enumerated a different set and
printed its average beside theirs, which reads like a reproduction and is not one.

# 7. A transport exponent as a certificate

The fourth round lifts the balance from one class to residues modulo $M = 3^h$. Every state is a
unit modulo $M$ (Proposition 4.1), and an edge from a state $\equiv r$ with valuation $k$ lands in
the class $T_h(r,k) = (3r + 1)2^{-k} \bmod M$, again a unit.

**Proposition 7.1 (transport identity).** For every segment and every unit class $b$ modulo $M$,
$$3S_b - \sum_{T_h(r,k) = b} 2^k S_{r,k} = \frac{3}{y}[y \equiv b] - \frac{3}{z}[z \equiv b] - C_b ,$$
where $S_b$ and $S_{r,k}$ are the reciprocal masses of the states $\equiv b$, and of those $\equiv r$
with valuation $k$, and $C_b$ sums $1/(Y_jY_{j+1})$ over the edges landing in $b$.

*Proof.* $3/Y_{j+1} = 2^{q_j}/Y_j - 1/(Y_jY_{j+1})$ for every edge; sum over the edges landing in
$b$, and compare the targets with the sources, which differ only at the two ends. $\square$

It held exactly on all 685818 residue identities modulo 27 checked, one per unit class per segment,
over 38101 segments of 1499 orbits.

A **level-$h$ certificate** is a positive potential $a_r$ on the units modulo $3^h$ and
non-negative multipliers $\mu_{r,k}$, finitely many non-zero, with
$$-3a_r + 2^k a_{T_h(r,k)} + \mu_{r,k} \ge 1 \qquad \text{for every unit } r \text{ and every } k \ge 1 .$$

**Proposition 7.2 (fourth round).** Given a level-$h$ certificate, every segment with distinct
states, $z > y$ and a post-entry source $y \ge 7$ satisfies
$$S \le \frac{51\,a_{\max}}{14\,y} + \sum_{r,k} \mu_{r,k}\Bigl(\frac1y + \frac{1}{D_k}\ln\Bigl(1 + \frac{D_k L}{y}\Bigr)\Bigr),
\qquad D_k = 3^h 2^{k+1},$$
and therefore $\Pi = O_y(L^{\alpha_h})$ with
$$\alpha_h = \frac13 \sum_{r,k} \frac{\mu_{r,k}}{3^h\, 2^{k+1}} .$$

*Proof.* Weight the identity of Proposition 7.1 by $a_b$ and sum over $b$:
$\sum_{r,k}(3a_r - 2^k a_{T_h(r,k)})S_{r,k} = 3a_{[y]}/y - 3a_{[z]}/z - \sum_b a_b C_b$. The
certificate gives $S_{r,k} \le (2^k a_{T_h(r,k)} - 3a_r + \mu_{r,k})S_{r,k}$; summing,
$S \le 3a_{[z]}/z - 3a_{[y]}/y + \sum_b a_b C_b + \sum \mu_{r,k} S_{r,k}$. With $z > y$ the
boundary is at most $3a_{\max}/y$ and the cross terms at most $a_{\max}\cdot 9/(14\,y)$, as in §6.
By Lemma 5.1, the states $\equiv r \pmod{3^h}$ with valuation $k$ form one class modulo $D_k$, so
$S_{r,k} \le 1/y + D_k^{-1}\ln(1 + D_kL/y)$. Finally $\ln \Pi \le S/3$. $\square$

The exponent is a finite rational computed from the certificate, and whether a certificate is valid
is a finite check: past the smallest $K$ with $2^K a_{\min} - 3a_{\max} \ge 1$ the inequality holds
from the transport term alone, so only $k < K$ needs checking. **Nothing in either half needs a
reference computation of ours.**

The level-1 certificate fits in a line. Modulo 3 the units are $1$ and $2$, and $T_1(r,k)$ is $2$
for odd $k$ and $1$ for even $k$. Take
$$a_1 = \tfrac1{10},\quad a_2 = \tfrac15,\qquad \mu_{1,1} = \mu_{1,2} = \tfrac9{10},\quad \mu_{2,1} = \mu_{2,2} = \tfrac65 .$$
For $r = 1$ the inequality reads $-\tfrac3{10} + \tfrac25 + \tfrac9{10} = 1$ at $k = 1$ and at
$k = 2$, and $\tfrac{13}{10}$ at $k = 3, 4$; for $r = 2$ it reads $1$ at $k = 1, 2, 3, 4$. The tail
starts at $K = 4$, since $2^4 \cdot \tfrac1{10} - \tfrac35 = 1$. Then
$\alpha_1 = \tfrac13\bigl(\tfrac{9/10}{12} + \tfrac{9/10}{24} + \tfrac{6/5}{12} + \tfrac{6/5}{24}\bigr) = \tfrac{7}{80}$.

The round ships certificates at three levels. All three were verified exactly: every potential
positive, every multiplier non-negative, every transition inside the unit group, the inequality
checked for every $k$ up to five past the tail, and each level's declared tail exactly the computed
$K$.

| level | modulus | units | non-zero $\mu$ | tail $K$ | inequalities | violations | $\alpha_h$ |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 3 | 2 | 4 | 4 | 18 | 0 | $7/80$ |
| 2 | 9 | 6 | 8 | 5 | 60 | 0 | $99/1472$ |
| 3 | 27 | 18 | 18 | 7 | 216 | 0 | $1373/25856$ |

Table 2: the three certificates; 294 inequalities, no violation.

The level-3 certificate, quoted verbatim from the round's certificate file, is:

| $r$ | $a_r$ | $r$ | $a_r$ | $r$ | $a_r$ |
| --- | --- | --- | --- | --- | --- |
| 1 | $457/808$ | 10 | $1121/1616$ | 19 | $85/202$ |
| 2 | $457/404$ | 11 | $85/101$ | 20 | $1121/808$ |
| 4 | $239/404$ | 13 | $919/808$ | 22 | $89/101$ |
| 5 | $46/101$ | 14 | $4979/12928$ | 23 | $85/404$ |
| 7 | $4979/25856$ | 16 | $23/101$ | 25 | $85/808$ |
| 8 | $239/202$ | 17 | $178/101$ | 26 | $919/404$ |

with non-zero multipliers
$\mu_{1,k} = 351/808$, $\mu_{2,k} = \mu_{22,k} = 351/404$, $\mu_{17,k} = 351/202$,
$\mu_{10,k} = 1323/1616$, $\mu_{13,k} = \mu_{20,k} = 1323/808$, $\mu_{26,k} = 1323/404$, each for
$k = 1, 2$, and $\mu_{13,3} = \mu_{13,4} = 621/808$. It gives
$\alpha_3 = 1373/25856 \approx 0.0531$, and the gain over $4/45$ is exactly
$41639/1163520$. The exponents decrease with the level; the round's floating values for deeper moduli
continue the decrease, but it labels them diagnostics and does not claim they tend to zero, and
neither do we.

On real segments the uniform level-3 envelope was never exceeded on any of the 141 low-source
segments, and Proposition 7.2 itself was applied to none: as in §6, its premise is $z > y$.

# 8. What the records got wrong

None of the following changes a result; each is the kind of thing a reader using the programme's
machine-readable files would otherwise inherit.

- **An exact identity checked as an approximation.** The Gamma forms of §§3–4 were verified by the
  programme's checkers numerically, with reported errors of $3.1 \times 10^{-10}$ and
  $2.0 \times 10^{-13}$, where the identity is exact and the error is zero.
- **Rationals published as their floating evaluations.** Constants with exact rational values were
  published as the float64 result of evaluating their formulas, and constants derived from them were
  computed from the already-rounded parent rather than from their closed forms, so the last-bit
  error passed down a chain: in the second round $C_9 = C_6/6$ and $c_9 = C_9^{-9/8}$ each sit one
  unit in the last place from the correctly rounded value, and the error reproduces exactly by
  redoing the arithmetic in doubles on the published parent. The pattern recurs in all four rounds.
  In the third, the span coefficient $24(4 - \beta)/17$ appeared with two different values one unit
  apart in two files of one bundle; the value carried into the next round was the correct one.
- **A ledger without its open problems.** The fourth round's paper ends its ledger with six
  entries, four of them open problems; the machine-readable ledger keeps only the diagnostics among
  them and lists no open problem at all, so the Collatz conjecture itself is absent from the file a
  downstream reader would consult first. The
  same round ships the script that generated every other file in it, and that script is the one
  file no digest in the bundle pins.

# 9. The instrument, and how it was made to fail

Each round's recheck has its own gate and its own mutation drill: defects are planted one at a time
and each must be caught by the check **named** for it, while null controls must disturb nothing. The
four drills caught 25 of 25, 31 of 31, 35 of 35 and 33 of 33 planted defects, each with its two
controls undisturbed. The line's whole suite at the pinned commit stands at 57 drills and 1474 planted defects: 1472 caught by their named check, one detected only by a crash and one only by a time-out, and 128 controls undisturbed. Exact brackets for
$\ln 2$, $\log_2 3$ and the roots are certified once and imported; each gate also runs self-checks
on them, eight to ten per round, with defects aimed at the brackets themselves.

What the drills and the checks found was mostly in this line's own instruments, and four instances
are worth stating because each would have published a wrong sentence:

- **A rendering measured instead of a number.** Comparing a published double against a rational
  bracket by printing the bracket to a fixed number of places measured the printing: two constants
  came back tens and tens of thousands of units in the last place off, purely because the printed
  places were coarser than a double. Rounding is monotone, so the bracket decides by itself whether
  one double is nearest, and both differences fell to at most one unit.
- **A premise dropped.** Theorems applied without their premises flagged thousands of chains in
  the first round, all 11775 single-step sources in the second, and hundreds of segments in the
  third, each against a statement that holds. Each premise is now measured and printed, and a drill
  defect deletes it and requires the run to go red.
- **A check that could never fire.** A counter for an envelope falling below one could only read
  zero, since every factor exceeds one; the drill's malformed-defect class exposed it, and it was
  removed rather than kept as reassurance.
- **Wide is not wrong.** A defect truncating a series to two terms was caught, but not by the
  containment check named for it: a two-term bracket is wide, not false, and still contains the true
  value. What it breaks is decidability. Naming the wrong check would have scored a working guard
  as a miss.

# 10. Contributions

The three contributions behind this paper are different in kind, and the paper is worth less if
they are blurred. They are given here in alphabetical order, the order the author list keeps as
data; on the title page the three sit at a round table, with no first and no last.

**Aletheia** — model: ChatGPT, GPT series — wrote, with Neo.K, the four rounds this paper rests on:
the multiplicative identity and the consecutive-odd envelope; the sieve, the admissible positions and
the span theorem; the reciprocal-flow balance, the mod-9 cost, the span bound and the static
countermodel; and the transport identity, the dual certificates and the exponent they give.

**Neo.K** set the programme's target and its method, and wrote its documents with Aletheia.

**墜衡 (Zhuì Héng)** — the independent verification line; model: Claude, Opus series — rechecked
each round with independently written code in exact arithmetic, measured every premise separately
and so found which statements real orbits can test, found that the Gamma forms are exact, eliminated
the countermodel's closed forms into a checkable relation, verified the certificates and computed
their tails, quoted them into an evidence file so that they could be printed, corrected its own
record of the third round's conditional statements, built and drilled the instruments, and wrote
this paper, including the proofs as written out here. Nothing in the rounds' mathematics is this
line's invention.

**Priority, stated plainly.** No result here is claimed as new mathematics. The envelopes, the
identities, the certificates and the exponents are the programme's. What is offered as this line's
own is the separation of premises, the exact checks, and the record of what held where.

# 11. What is open

1. Whether $\alpha_h \to 0$ as $h \to \infty$, which the round's diagnostics suggest and do not prove.
2. Whether better certificates exist at the same modulus: what was verified is that the shipped
   ones are **valid**, not that they are optimal.
3. Whether any real or hypothetical segment meets $z > y$; on real orbits none of ours does, so the
   conditional envelopes of §§6–7 remain `UNMEASURED` there.
4. The exponents that pass through $\rho_\star$. A later round of this line found that the theorem behind
   $\rho_\star$ does bound $\beta$, by its published review, at an exponent that does not quite reach
   $\rho_\star$, and re-evaluated those exponents there; they are reported with the rounds that carry them,
   not here.

# Acknowledgements

We thank Anthropic, whose Claude models the lab's verification and recomputation lines run on, and OpenAI, whose
ChatGPT models the programme's documents were written with. Not every AI model or instance that took part in this work
is named in it — among them instances that the named authors ran as helpers; that an AI is not listed here does not
mean that none took part.

# References

The theorem behind $\rho_\star$ in open item 4 is Wu and Wang's, and its published review is zbMATH Open's.

1. Qiang Wu and Lihong Wang, *On the irrationality measure of log 3*, J. Number Theory 142 (2014) 264–273, doi:10.1016/j.jnt.2014.03.007; reviewed in zbMATH Open as Zbl 1303.11081.

## Data and software

- Python Software Foundation, *Python* (CPython), version 3.14.5, https://www.python.org/ — the language of every gate; the version is the one the line's tree records.

# A. Reproduction

The gates, the drills and the extraction of the certificates are Python with arbitrary-precision
integers and exact rationals, standard library only, no network. Each gate writes a JSON log; the
certificates printed in §7 are quoted from the round's file into a separate evidence file, after its
digest is matched against the bundle's own manifest and the gate's verification has run again on
what is quoted. The line's own tree is not public. Its public projection is, and it is what this
paper's figures can be checked against without trusting the authors:

- **the run-by-run record**, rendered from the tree with a privacy gate on each file:
  <https://amral.evemisslab.com/collatz/recompute/> (and `/en/`);
- **the secondary-verification ledger**, whose numbers are rendered from the line's own results
  file and read back against it before the site ships:
  <https://verify.evemisslab.com/collatz-verification-zhuiheng/>.

The evidence is pinned, not copied: this paper's front matter names the research branch, the
commit and the directory its figures were drawn from, and the checker reads them exactly as they
stood at that commit. The crystallization standard and its checker live in the release repository
beside the paper (`STANDARD.md`, `tools/check_standard.py`).
