> Full-text translation from Chinese. The original remains authoritative for its research claims; this translation is not independent mathematical verification.

# TCDC-05
## Quarter-Root Weighted Pressure / Chen-Lemma Adaptation
### Strict-Semiprime Half-Weight, Medium-Divisor Multiplicity, Extra Prime-Branch Cost, Constant Gate and Balanced-Convolution Provider Map

**Parent methodology:** TCDC — Target–Condition Dual Closure  
**Connected research lines:** RG-SCP / SRBRD  
**Round:** TCDC-05  
**Date:** 2026-10-02  
**Version:** v0.1  
**Authors:** Neo.K; Aletheia (GPT-5.6 Sol)  
**Nature:** Pointwise Weighted-Sieve Lemma / Chen-Type Adaptation / Constant Audit  
**Prerequisites:** TCDC-00 ～ TCDC-04; SRBRD-00 ～ SRBRD-26  
**Status:** Establishes a quarter-root Chen-type pointwise lower weight for strict semiprime pressure; proves that the half-weight coefficient is minimal within the natural linear ansatz; the standard $3/5$ linear-sieve main constant retains a small positive margin after subtracting the half medium-divisor term, but the prime branch and exactly-one-medium correction remain unclosed; Goldbach remains unproved

---

# 0. Goals of This Round

TCDC-04 has written high-suffix pressure as:

$$
\boxed{
\Pi_\lambda
=
S_\lambda(z)-P_\lambda,
}
$$

where:

- $S_\lambda(z)$：
  the complement $y=2m-rp$ passes cube-root RootRough;
- $P_\lambda$：
  those among them for which $y$ is prime;
- $\Pi_\lambda$：
  the strict semiprime branch.

Directly using:

$$
z=X^{1/3}
$$

the lower linear sieve requires:

$$
\theta>2/3,
$$

Thus the current:

$$
3/5
$$

and even:

$$
5/8
$$

cannot directly carry the lower sieve all the way through.

TCDC-04 therefore instead uses:

$$
\boxed{
w=X^{1/4}
}
$$

as a coarse cutoff,

such that:

$$
\operatorname{RootRough}_w(y)
$$

allowing only:

$$
P_1,\ P_2,\ P_3.
$$

The goal of TCDC-05:

> Within this finite factor-depth domain,
> establish a genuinely pointwise Chen-type weight
> that directly lower-bounds:
> $$
> \mathbf1_{\{
> y\text{ strict semiprime},
> \operatorname{lpf}(y)>z
> \}}.
> $$

---

# 1. Basic Scales

Let:

$$
X=2m-3.
$$

Define:

$$
\boxed{
w=X^{1/4},
}
$$

and the cube-root cutoff:

$$
\boxed{
z=z_3(m),
\qquad
z^3\ge X.
}
$$

High-suffix base:

$$
\boxed{
\mathcal A_\lambda
=
\left\{
(r,p):
r,p\in\mathbb P,
\quad
r\ge\lambda\sqrt m,
\quad
p\ge r,
\quad
rp\le X
\right\}.
}
$$

Complement:

$$
\boxed{
y=2m-rp.
}
$$

---

# 2. Desired Pressure Indicator

Define:

$$
\boxed{
H_z(y)
=
\mathbf1_{\{
y\text{ semiprime},
\operatorname{RootRough}_z(y)
\}}.
}
$$

For composite:

$$
y,
$$

this is equivalent to:

$$
\boxed{
y=q_1q_2,
\qquad
q_1,q_2\in\mathbb P,
\qquad
z<q_1\le q_2.
}
$$

---

# 3. Desired Strict Semiprimes Automatically Lie Above $z^2$

If:

$$
H_z(y)=1,
$$

then:

$$
y=q_1q_2,
$$

$$
q_1,q_2>z.
$$

Thus:

## Theorem TCDC-05-T01

$$
\boxed{
H_z(y)=1
\Longrightarrow
y>z^2.
}
$$

Therefore:

$$
y\le z^2
$$

cannot contribute to strict semiprime pressure at all.

This is structurally compatible with the classical Chen lemma often working in the:

$$
n>x^{2/3}
$$

region.

---

# 4. Quarter-Root Factor Depth

If:

$$
\operatorname{RootRough}_w(y)
$$

and:

$$
y
$$

is composite,

then:

$$
\operatorname{lpf}(y)>w.
$$

If:

$$
\Omega_{\mathrm{mult}}(y)\ge4,
$$

then:

$$
y>w^4=X,
$$

a contradiction.

Thus:

## Theorem TCDC-05-T02

$$
\boxed{
\operatorname{RootRough}_w(y)
\Longrightarrow
y\in
\mathbb P
\cup
P_2
\cup
P_3.
}
$$

---

# 5. Medium-Prime Multiplicity

Define:

$$
\boxed{
\nu_{w,z}(y)
=
\sum_{\substack{
\ell\in\mathbb P\\
w<\ell\le z
}}
v_\ell(y),
}
$$

where:

$$
v_\ell(y)
$$

is the prime-factor multiplicity of $\ell$ in $y$.

Since:

$$
\Omega_{\mathrm{mult}}(y)\le3
$$

in the coarse composite domain,

Thus:

$$
\boxed{
0\le\nu_{w,z}(y)\le3.
}
$$

For prime:

$$
y,
$$

If:

$$
w<y\le z,
$$

then:

$$
\nu_{w,z}(y)=1.
$$

This causes no problem,

because the prime branch is subtracted separately.

---

# 6. Exactly-One-Medium Composite State

Define:

$$
\boxed{
E_1(y)
=
\mathbf1_{\{
y\text{ composite},
\operatorname{RootRough}_w(y),
\nu_{w,z}(y)=1
\}}.
}
$$

This is the:

# Exactly-One-Medium Correction

---

# 7. Strict-Semiprime Half-Weight

Define the pointwise weight:

$$
\boxed{
\omega_{w,z}(y)
=
\mathbf1_{\operatorname{RootRough}_w(y)}
\left[
1
-
\mathbf1_{\mathbb P}(y)
-
\frac12\nu_{w,z}(y)
-
\frac12E_1(y)
\right].
}
$$

---

# 8. Main Pointwise Lemma

## Theorem TCDC-05-T03
### Strict-Semiprime Chen Weight

For:

$$
3\le y\le X,
$$

we have:

$$
\boxed{
\omega_{w,z}(y)
\le
H_z(y).
}
$$

Therefore:

$$
\boxed{
H_z(y)
\ge
\omega_{w,z}(y).
}
$$

---

# 9. T03 Case Audit — Prime

If:

$$
y\in\mathbb P,
$$

then:

$$
H_z(y)=0.
$$

And:

$$
\omega_{w,z}(y)
=
-\frac12
\mathbf1_{\{w<y\le z\}}
\le0.
$$

Thus the claim holds.

---

# 10. T03 Case Audit — Desired $P_2$

If:

$$
y=q_1q_2,
$$

$$
z<q_1\le q_2,
$$

then:

$$
\operatorname{RootRough}_w(y)=1,
$$

$$
\nu_{w,z}(y)=0,
$$

$$
E_1(y)=0,
$$

$$
\mathbf1_{\mathbb P}(y)=0.
$$

Thus:

$$
\boxed{
\omega_{w,z}(y)=1=H_z(y).
}
$$

The desired branch receives exact unit weight.

---

# 11. T03 Case Audit — Medium $P_2$

If:

$$
y
$$

is semiprime,

However:

$$
\operatorname{lpf}(y)\le z,
$$

within the coarse RootRough$_w$ domain:

$$
\nu_{w,z}(y)\ge1.
$$

### multiplicity $1$

$$
\nu=1,
\quad
E_1=1,
$$

Thus:

$$
\omega=1-\frac12-\frac12=0.
$$

### multiplicity $2$

$$
\nu=2,
\quad
E_1=0,
$$

Thus:

$$
\omega=1-1=0.
$$

Thus undesired medium $P_2$ receives no positive weight.

---

# 12. T03 Case Audit — $P_3$

If:

$$
y
$$

is $P_3$ and RootRough$_w$.

Since:

$$
z^3\ge X\ge y
$$

and if all three prime factors are:

$$
>z,
$$

then:

$$
y>z^3\ge X,
$$

a contradiction.

Thus:

$$
\nu_{w,z}(y)\ge1.
$$

### $\nu=1$

$$
E_1=1,
$$

Thus:

$$
\omega=0.
$$

### $\nu=2$

$$
\omega=0.
$$

### $\nu=3$

$$
\omega=-1/2.
$$

Therefore:

$$
\boxed{
P_3
\text{ never receives positive pressure weight}.
}
$$

This completes the proof of T03.

---

# 13. Why the Half Coefficient Is Forced

Consider the natural linear ansatz:

$$
\boxed{
1
-
a\nu
-
b\mathbf1_{\{\nu=1\}}
}
$$

Considering only composite coarse states,

we want all bad states:

$$
\nu=1,2,3
$$

to have weight:

$$
\le0.
$$

Constraints:

### $\nu=1$

$$
1-a-b\le0.
$$

### $\nu=2$

$$
1-2a\le0.
$$

### $\nu=3$

$$
1-3a\le0.
$$

Thus:

## Theorem TCDC-05-T04
### Half-Weight Optimality

$$
\boxed{
a\ge1/2.
}
$$

If we take the minimum:

$$
a=1/2,
$$

then:

$$
\boxed{
b\ge1/2.
}
$$

Therefore:

$$
\boxed{
(a,b)=(1/2,1/2)
}
$$

is the componentwise minimal admissible choice for this two-statistic linear ansatz.

Thus half-weight is not an arbitrary imitation of Chen.

---

# 14. Structure of $E_1$

Since:

$$
E_1
$$

requires compositeness and medium multiplicity exactly:

$$
1,
$$

within the coarse:

$$
P_2/P_3
$$

domain it splits into exactly:

## Medium-$P_2$ Branch

$$
\boxed{
y=\ell q,
}
$$

$$
w<\ell\le z<q,
$$

with primes:

$$
\ell,q.
$$

## Triple Branch

$$
\boxed{
y=\ell q_2q_3,
}
$$

$$
w<\ell\le z<q_2\le q_3,
$$

with prime factors.

A square:

$$
\ell^2
$$

is not in $E_1$,

because its multiplicity is:

$$
2.
$$

This is precisely the benefit of using multiplicity rather than distinct divisor count.

---

# 15. Define the Weighted Counts

High-suffix coarse survivor:

$$
\boxed{
A_1
=
S_\lambda(w).
}
$$

Prime branch:

$$
\boxed{
A_P
=
P_\lambda.
}
$$

Medium multiplicity term:

$$
\boxed{
A_2
=
\sum_{\substack{
(r,p)\in\mathcal A_\lambda\\
\operatorname{RootRough}_w(y)
}}
\nu_{w,z}(y).
}
$$

Exactly-one-medium $P_2$:

$$
\boxed{
A_{2,1}
=
\#\{
(r,p):
y=\ell q,
\ w<\ell\le z<q
\}.
}
$$

Exactly-one-medium $P_3$:

$$
\boxed{
A_{3,1}
=
\#\{
(r,p):
y=\ell q_2q_3,
\ w<\ell\le z<q_2\le q_3
\}.
}
$$

Then:

$$
\boxed{
\sum E_1
=
A_{2,1}+A_{3,1}.
}
$$

All sums are restricted to:

$$
(r,p)\in\mathcal A_\lambda
$$

and to the coarse RootRough condition when required.

---

# 16. Summed Strict-Pressure Lemma

Summing T03 gives:

## Theorem TCDC-05-T05

$$
\boxed{
\Pi_\lambda
\ge
A_1
-
A_P
-
\frac12A_2
-
\frac12A_{2,1}
-
\frac12A_{3,1}.
}
$$

This is the main weighted inequality of this round.

---

# 17. Compare with the Exact Buchstab Identity

TCDC-04 gives the exact identity:

$$
\boxed{
\Pi_\lambda
=
S_\lambda(w)
-
B_\lambda(w,z)
-
P_\lambda.
}
$$

T05 uses:

$$
A_2,
A_{2,1},
A_{3,1}
$$

in place of the difficult OR-event:

$$
B_\lambda(w,z).
$$

Thus:

> T05 is a proof-friendly lower relaxation,
> whereas TCDC-04 is an exact least-factor identity.

---

# 18. Exact Medium-Divisor Inclusion–Exclusion

For composite RootRough$_w$:

$$
\nu=\nu_{w,z}(y)\in\{0,1,2,3\}.
$$

we have the exact identity:

$$
\boxed{
\mathbf1_{\{\nu\ge1\}}
=
\nu
-
\binom{\nu}{2}
+
\binom{\nu}{3}.
}
$$

Thus shell loss can also be written as a finite hyperintersection expansion.

This gives another route:

$$
\boxed{
B
=
D_1-D_2+D_3.
}
$$

However:

- $D_1$ requires an upper bound;
- $D_2$ has a positive sign and requires a lower bound;
- $D_3$ again requires an upper bound.

The half-weight in T05 avoids directly requesting a:

$$
D_2
$$

lower bound,

at the cost of adding an:

$$
E_1
$$

upper cost.

---

# 19. Half-Weight Identity Behind T05

For:

$$
\nu=0,1,2,3,
$$

we have:

$$
\boxed{
\mathbf1_{\{\nu\ge1\}}
=
\frac12\nu
+
\frac12\mathbf1_{\{\nu=1\}}
-
\frac12\mathbf1_{\{\nu=3\}}.
}
$$

Thus:

$$
\boxed{
B
\le
\frac12D_1
+
\frac12E_1.
}
$$

dropping the favorable:

$$
+\frac12E_3
$$

recovery.

T05 is precisely this pointwise relaxation.

---

# 20. Difference from Classical Chen's Lemma

The classical Chen lower-weight lemma for:

$$
1_{\mathcal P_2}(n)
$$

uses:

- coefficient：
  $$
  1/2
  $$
  on the medium-prime divisor term;
- a triple-factor correction;
- a square-factor correction.

Its target:

$$
\mathcal P_2
$$

includes:

- primes;
- semiprimes.

By contrast, this TCDC target is:

$$
\boxed{
\text{strict semiprime with lpf}>z.
}
$$

Thus we must additionally pay for:

## Extra Cost I

$$
\boxed{
A_P
}
$$

the prime branch.

## Extra Cost II

$$
\boxed{
A_{2,1}
}
$$

the medium-$P_2$ branch.

These two costs are not bad states for the classical Chen target.

Therefore:

$$
\boxed{
\text{strict-pressure problem is combinatorially stricter than Chen's }P_2\text{ problem}.
}
$$

---

# 21. Square Correction Is Absorbed by Multiplicity

The classical Chen formulation needs an explicit:

$$
p^2\mid n
$$

correction,

because it uses divisor indicators rather than multiplicity bookkeeping.

This round defines:

$$
\nu_{w,z}(y)
=
\sum v_\ell(y).
$$

Thus:

- $\ell^2$ automatically contributes:
  $$
  2;
  $$
- $\ell^3$ contributes:
  $$
  3.
  $$

Thus square / cube multiplicity is already built into:

$$
A_2.
$$

This simplifies the TCDC-tailored weight.

---

# 22. Coarse Lower-Sieve Constant at Current $3/5$

Assume a proof-admissible dimension-1 lower-sieve provider with:

$$
D=X^{3/5},
$$

$$
w=X^{1/4}.
$$

then:

$$
\boxed{
s_0
=
\frac{\log D}{\log w}
=
\frac{12}{5}.
}
$$

The classical lower function:

$$
f_1(s)
=
\frac{
2e^\gamma
}{s}
\log(s-1)
$$

for:

$$
2\le s\le4.
$$

Thus:

## Diagnostic TCDC-05-D01

$$
\boxed{
C_{\mathrm{coarse}}
=
f_1(12/5)
=
\frac{
5e^\gamma
}{6}
\log\frac75
}
$$

$$
\boxed{
C_{\mathrm{coarse}}
\approx
0.499401183388.
}
$$

---

# 23. Medium-Divisor First-Order Upper Integral

Let:

$$
\ell=X^u,
$$

$$
\frac14\le u\le\frac13.
$$

Conditioning on:

$$
\ell\mid y
$$

reduces the available sieve level approximately to:

$$
D/\ell.
$$

Relative to:

$$
w=X^{1/4},
$$

the parameter is:

$$
\boxed{
s_\ell
=
4
\left(
\frac35-u
\right).
}
$$

Its range:

$$
\boxed{
16/15
\le
s_\ell
\le
7/5.
}
$$

The upper linear sieve:

$$
F_1(s)
=
\frac{
2e^\gamma
}{s}
$$

for:

$$
1<s\le3.
$$

---

# 24. Integrated Medium-Divisor Constant

Formal first-order normalized integral:

$$
\boxed{
C_{\mathrm{med}}
=
\int_{1/4}^{1/3}
F_1
\left(
4(3/5-u)
\right)
\frac{du}{u}.
}
$$

Direct integration gives:

## Theorem TCDC-05-T06

$$
\boxed{
C_{\mathrm{med}}
=
\frac{
5e^\gamma
}{6}
\log\frac74
}
$$

and:

$$
\boxed{
C_{\mathrm{med}}
\approx
0.830596870470.
}
$$

This is a constant diagnostic;

an actual theorem still requires:

- sequence distribution;
- a local singular factor;
- remainder control.

---

# 25. Why Coefficient $1$ Fails

If we use the simplest bound:

$$
\Pi
\ge
A_1-A_P-A_2,
$$

even ignoring:

$$
A_P,
$$

the constant is already:

$$
\boxed{
C_{\mathrm{coarse}}
-
C_{\mathrm{med}}
\approx
-0.331195687082
<0.
}
$$

Thus:

## Barrier TCDC-05-B01

$$
\boxed{
\text{full medium-divisor subtraction has the wrong sign
before prime / triple costs are even paid}.
}
$$

---

# 26. Half-Weight Restores a Positive Window

T05 pays only:

$$
\frac12A_2.
$$

Thus the coarse-minus-medium constant is:

$$
\boxed{
C_*
=
C_{\mathrm{coarse}}
-
\frac12
C_{\mathrm{med}}.
}
$$

Numerically:

## Diagnostic TCDC-05-D02

$$
\boxed{
C_*
\approx
0.084102748153
>0.
}
$$

That is:

$$
\boxed{
0.0841\text{ normalized units}
}
$$

a positive window of approximately this size.

---

# 27. The New Strict-Pressure Constant Gate

T05 still needs to pay:

$$
A_P
+
\frac12A_{2,1}
+
\frac12A_{3,1}.
$$

Thus if all terms have constants on the same normalized base scale:

$$
C_P,
$$

$$
C_{2,1},
$$

$$
C_{3,1},
$$

we require:

## Theorem Template TCDC-05-T07

$$
\boxed{
C_P
+
\frac12C_{2,1}
+
\frac12C_{3,1}
<
C_*
}
$$

to obtain positive weighted pressure.

The current diagnostic:

$$
\boxed{
C_*
\approx
0.0841.
}
$$

This is a very thin constant budget.

---

# 28. Why This Is Harder Than Classical Chen

The classical Chen $P_2$ ledger need not subtract:

$$
A_P
$$

because primes are acceptable,

and need not subtract the medium:

$$
P_2
$$

branch:

$$
A_{2,1}.
$$

Our strict pressure ledger needs both.

Thus:

$$
\boxed{
\text{the same half-weight that is effective for Chen
leaves a much tighter residual budget here}.
}
$$

This is the most important quantitative warning of this round.

---

# 29. Balanced Nature of the Base Variables

High suffix:

$$
r\ge\lambda\sqrt m,
$$

and:

$$
p\ge r,
$$

$$
rp\le2m.
$$

Thus:

$$
\boxed{
r,p
\asymp
X^{1/2}
}
$$

up to constants depending on:

$$
\lambda.
$$

Therefore:

$$
\boxed{
rp\equiv2m\pmod d
}
$$

is a balanced prime-product convolution.

---

# 30. Maynard-III Balanced Type-II Shape Match

Maynard-III Proposition 5.3 specifically treats balanced convolutions:

$$
N,M\approx x^{1/2}
$$

with modulus:

$$
q_1q_2
$$

and residue compatibility:

$$
a\equiv b\pmod{q_1}.
$$

For the global Goldbach shift:

$$
A=2m,
$$

Take:

$$
a=A\bmod q_1q_2,
$$

$$
b=A\bmod q_1,
$$

compatibility is automatic.

Thus:

## Theorem-Match TCDC-05-M01

$$
\boxed{
\text{the high-suffix base has the correct balanced-convolution shape
for Maynard-III Proposition 5.3}.
}
$$

However, this is still not a direct sieve provider.

---

# 31. Why Proposition 5.3 Is Not Yet $A_1$

The coarse lower bound:

$$
A_1=S_\lambda(w)
$$

requires:

- lower linear-sieve weights;
- squarefree moduli up to:
  $$
  D\approx X^{3/5};
  $$
- a suitable factorization decomposition;
- a remainder sum with the correct sign / norm.

Proposition 5.3 provides only a mean-value discrepancy for certain factorized moduli.

Thus:

$$
\boxed{
\text{balanced convolution shape PASS}
\neq
\text{coarse lower-sieve provider PASS}.
}
$$

---

# 32. Medium Divisor Term as Convolution-Sieve Sequence

The condition:

$$
\ell\mid y
$$

is equivalent to:

$$
\boxed{
rp\equiv2m\pmod\ell.
}
$$

with:

$$
w<\ell\le z.
$$

If we additionally sieve the remaining complement by small primes:

$$
d,
$$

the modulus becomes:

$$
\ell d.
$$

Therefore:

$$
A_2
$$

requires mean distribution for:

$$
\boxed{
rp\equiv2m
\pmod{\ell d}.
}
$$

This is precisely a:

# Balanced Prime-Product Convolution with a Medium Forced Factor

---

# 33. Yang 2026 Shape Interface

Yang 2026 proves convolution-type Bombieri–Vinogradov estimates with well-factorable / upper linear-sieve weights for expressions of the form：

$$
lp\equiv a\pmod q.
$$

Thus in:

# convolution shape

and:

# upper-weight polarity

it is very close to:

$$
A_2
$$

as displayed above.

However, in the audited theorem the residue:

$$
a
$$

remains a fixed parameter,

whereas in this problem:

$$
a=2m\asymp X.
$$

Thus:

## Theorem-Match TCDC-05-M02

$$
\boxed{
\text{Yang 2026 is a medium-term technology template,
not a legal uniform Goldbach-shift provider as currently stated}.
}
$$

---

# 34. The $A_{2,1}$ Term

$$
A_{2,1}
$$

counts:

$$
\boxed{
2m
=
rp
+
\ell q,
}
$$

with four prime variables:

$$
r,p,\ell,q,
$$

and ranges:

$$
r,p\asymp\sqrt X,
$$

$$
X^{1/4}<\ell\le X^{1/3},
$$

$$
q>X^{1/3}.
$$

This is not the classical Chen triple-factor cost.

It is a:

# Two-Product Additive Correlation

and is a new term introduced by the strict-pressure adaptation.

---

# 35. The $A_{3,1}$ Term

$$
A_{3,1}
$$

counts:

$$
\boxed{
2m
=
rp
+
\ell q_2q_3,
}
$$

where:

$$
w<\ell\le z<q_2\le q_3.
$$

This is closest to the classical Chen:

# Triple-Factor Bad Term

as displayed above.

The switching principle is very likely the natural treatment.

---

# 36. Prime Branch $A_P$

$$
A_P
$$

counts:

$$
\boxed{
2m
=
rp+q,
}
$$

with:

$$
r,p,q\in\mathbb P,
$$

$$
r\ge\lambda\sqrt m.
$$

This is a ternary prime correlation,

but requires only an:

$$
\boxed{
\text{upper bound}.
}
$$

Thus the parity polarity is easier than a direct Goldbach lower bound.

However, its constant must be very sharp,

because the residual budget is only:

$$
\approx0.0841.
$$

---

# 37. A New Three-Cost Architecture

The strict HSP weighted ledger now splits precisely into:

## Cost P

Prime complement:

$$
A_P.
$$

## Cost M2

Exactly-one-medium semiprime:

$$
A_{2,1}.
$$

## Cost T3

Exactly-one-medium triple:

$$
A_{3,1}.
$$

Thus:

$$
\boxed{
\text{strict HSP}
=
\text{Chen-like core}
-
\text{Prime Cost}
-
\text{Medium-}P_2\text{ Cost}.
}
$$

This is the largest structural difference from classical Chen.

---

# 38. Potential Improvement I — Exact Shell Instead of Half-Weight

TCDC-04 exact：

$$
\Pi
=
S_w-P-B.
$$

If we can directly upper-bound:

$$
B
$$

more sharply than:

$$
\frac12A_2+\frac12E_1
$$

as displayed above,

we can relax the:

$$
0.0841
$$

budget.

Thus half-weight is not the final optimal architecture.

It is only the:

# first proof-friendly Chen adaptation.

---

# 39. Potential Improvement II — Medium-Divisor Overlap Recovery

Exact finite inclusion–exclusion:

$$
B
=
D_1-D_2+D_3.
$$

Half-weight discards part of the positive:

$$
D_2
$$

recovery.

If we can lower-bound:

$$
D_2-D_3,
$$

we can improve the pressure constant.

This reconnects with the earlier SRBRD overlap philosophy.

---

# 40. Potential Improvement III — Global Prime-Sink Budget

The prime branch:

$$
A_P
$$

is precisely the high-suffix mixed transport:

$$
M_{r,0}.
$$

The TCDC-01 failure surface also has the global constraint:

$$
\boxed{
\sum_rM_{r,0}=n_P.
}
$$

Thus:

$$
A_P
$$

need not necessarily be paid entirely through a separate analytic ternary-prime upper bound.

It may be coupled with:

- low-row prime usage;
- the mirror receiver;
- center locks;

in a global transport budget.

This is an improvement direction specific to TCDC.

---

# 41. Potential Improvement IV — Optimize $w=X^{1/u}$

The quarter-root choice:

$$
u=4
$$

is not necessarily optimal.

In general:

$$
s=u\theta.
$$

Coarse lower bound:

$$
f_1(u\theta).
$$

Medium shell:

$$
u^{-1}<\log_X\ell\le1/3.
$$

Changing it changes:

- the lower-sieve constant;
- the shell width;
- the factor-depth complexity;
- the exactly-one-medium costs.

Thus we can define:

# Pressure Weight Optimization in $u$

However, this round first fixes:

$$
u=4.
$$

---

# 42. Pointwise Weight Can Be Machine-Verified

Since the coarse factor depth is at most:

$$
3,
$$

T03 only needs to check a finite state table:

- prime;
- $P_2$ with $\nu=0,1,2$;
- $P_3$ with $\nu=1,2,3$.

Thus:

$$
\boxed{
\text{weight admissibility is a finite symbolic problem}.
}
$$

In the future a solver can search for better linear / nonlinear weights.

---

# 43. Weight-Optimization LP

Define features:

$$
\boxed{
\phi(y)
=
(
1,
\mathbf1_{\mathbb P},
\nu,
\mathbf1_{\nu=1},
\mathbf1_{\nu=2},
\mathbf1_{\nu=3},
\ldots
).
}
$$

Search for coefficients:

$$
c
$$

such that:

$$
\boxed{
c\cdot\phi(y)
\le
H_z(y)
}
$$

for all coarse factor states.

Objective:

> maximize the estimated analytic main constant.

Thus:

# Chen-Weight Design Itself Becomes an LP

This fits TCDC / AI proof-operator synthesis very well.

---

# 44. T03 Weight as the First LP Solution

Restrict the features to:

$$
\boxed{
1,
\mathbf1_{\mathbb P},
\nu,
\mathbf1_{\{\text{composite},\nu=1\}}
}
$$

and fix the target coefficient:

$$
1,
$$

then T04 proves that:

$$
\boxed{
1/2,\ 1/2
}
$$

are the minimal penalty coefficients.

Thus T03 can be viewed as the:

# Minimal Four-Feature Pressure Weight

---

# 45. Finite Computational Calibration

This serves only as finite evidence.

Take:

$$
\lambda=1.1.
$$

Define the weighted lower bound:

$$
\boxed{
W_\lambda
=
A_1
-
A_P
-
\frac12A_2
-
\frac12E_1.
}
$$

and the crude bound:

$$
\boxed{
W_\lambda^{simple}
=
A_1-A_P-A_2.
}
$$

Selected exact enumerations:

| $m$ | $\lambda$ | $A_1$ | $A_P$ | $\Pi_\lambda$ | $A_2$ | $E_1$ | $W_\lambda$ | $W_\lambda^{simple}$ |
|---:|---:|---:|---:|---:|---:|---:|---:|---:|
| 1000 | 1.10 | 5 | 4 | 0 | 1 | 1 | 0.0 | 0 |
| 5000 | 1.10 | 9 | 5 | 2 | 2 | 2 | 2.0 | 2 |
| 10000 | 1.10 | 11 | 9 | 0 | 2 | 2 | 0.0 | 0 |
| 50000 | 1.10 | 51 | 32 | 7 | 15 | 10 | 6.5 | 4 |

All sampled cases satisfy:

$$
\boxed{
W_\lambda
\le
\Pi_\lambda.
}
$$

For the example:

$$
m=50000
$$

the weighted bound:

$$
W_\lambda=6.5
$$

is closer to:

$$
\Pi_\lambda=7,
$$

than the crude bound:

$$
4
$$

as displayed above.

Finite evidence cannot be promoted to a uniform theorem.

---

# 46. Why Fractional Weight Is Fine

$$
W_\lambda
$$

can be a half-integer.

This causes no problem.

As long as:

$$
\boxed{
W_\lambda>0,
}
$$

And:

$$
W_\lambda\le\Pi_\lambda,
$$

we obtain:

$$
\Pi_\lambda>0.
$$

Thus a weighted certificate need not be integer-valued.

---

# 47. Correct Polarity of Every Term

T05：

$$
\Pi
\ge
A_1
-
A_P
-
\frac12A_2
-
\frac12A_{2,1}
-
\frac12A_{3,1}.
$$

Thus the provider directions are:

### $A_1$

requires a:

$$
\boxed{
\text{lower bound}.
}
$$

### $A_P$

requires an:

$$
\boxed{
\text{upper bound}.
}
$$

### $A_2$

requires an:

$$
\boxed{
\text{upper bound}.
}
$$

### $A_{2,1}$

requires an:

$$
\boxed{
\text{upper bound}.
}
$$

### $A_{3,1}$

requires an:

$$
\boxed{
\text{upper bound}.
}
$$

Apart from the coarse survivor,

all the others have upper polarity.

This is a very favorable proof architecture.

---

# 48. Why This Still Does Not Automatically Beat Parity

The prime branch:

$$
A_P
$$

and the strict pressure:

$$
\Pi
$$

compete on the same:

$$
m/\log^3m
$$

scale.

If the upper sieve for:

$$
A_P
$$

carries the classical factor:

$$
2,
$$

it may directly consume the entire:

$$
0.0841
$$

window.

Thus:

$$
\boxed{
\text{the strict-prime subtraction is the new parity-sensitive constant bottleneck}.
}
$$

---

# 49. TCDC Interpretation

### Target

$$
\Pi_\lambda>0.
$$

### Enlarged Domain

Quarter-root RootRough:

$$
P_1/P_2/P_3.
$$

### Pointwise Proof Operator

$$
\omega_{w,z}(y).
$$

### Bad Branches

- prime;
- medium $P_2$;
- $P_3$.

### Weighted Closure

If the weighted total:

$$
W_\lambda>0,
$$

then target pressure exists.

This is a complete instance of TCDC-00:

# Reverse Domain Enlargement → Weighted Closure to Target

as displayed above.

---

# 50. Formal Theorem Queue

```yaml
TCDC_05:

  T01:
    desired_semiprime_above_z_squared

  T02:
    quarter_root_factor_depth_at_most_3

  T03:
    strict_semiprime_Chen_weight_pointwise

  T04:
    half_weight_optimality_in_two_statistic_ansatz

  T05:
    summed_weighted_pressure_lower_bound

  T06:
    medium_divisor_integrated_constant

  T07:
    strict_pressure_constant_gate
```

---

# 51. External Match Queue

```yaml
External_Match:

  MaynardIII_Prop5_3:
    balanced_prime_product_shape:
      PASS
    direct_lower_sieve_provider:
      NOT_YET

  Yang_2026:
    convolution_shape_for_medium_divisor:
      NEAR_MATCH
    growing_Goldbach_residue:
      MISMATCH_IN_AUDITED_STATEMENT

  Chen_classical:
    half_weight_philosophy:
      MATCH
    direct_strict_semiprime_target:
      NO
    extra_prime_cost:
      absent_classically
    extra_medium_P2_cost:
      absent_classically
```

---

# 52. Barrier Queue

```yaml
TCDC_05_Barriers:

  B01:
    full_medium_subtraction_negative_constant

  B02:
    half_weight_margin_only_about_0_0841

  B03:
    prime_branch_upper_cost_not_closed

  B04:
    exactly_one_medium_P2_cost_not_closed

  B05:
    triple_branch_switching_not_closed

  B06:
    balanced_convolution_lower_sieve_weight_match_not_closed

  B07:
    Goldbach_shift_uniform_convolution_provider_incomplete
```

---

# 53. Acceptance Gate

Before the TCDC-05 formal core, we need:

1. the $H_z$ strict target definition;
2. multiplicity, not distinct-factor count;
3. the coarse factor-depth proof;
4. all prime/P2/P3 cases checked;
5. the half-weight optimality proof;
6. $E_1$ split into medium P2 / P3;
7. square multiplicity handling;
8. weighted sum polarity;
9. the linear-sieve constant audit labeled diagnostic unless the provider is proved;
10. the difference from classical Chen stated explicitly;
11. Maynard/Yang only shape-matched where legal;
12. finite calibration labeled computational;
13. no HSP proof claim;
14. no Goldbach proof claim.

---

# 54. Verdict

This round can formally give:

$$
\boxed{
\mathrm{TCDC\mbox{-}05\ STRICT\mbox{-}SEMIPRIME\ HALF\mbox{-}WEIGHT\ PASS}.
}
$$

The most important pointwise lemma:

$$
\boxed{
H_z(y)
\ge
\mathbf1_{\operatorname{RootRough}_w(y)}
\left[
1
-
\mathbf1_{\mathbb P}(y)
-
\frac12\nu_{w,z}(y)
-
\frac12E_1(y)
\right].
}
$$

where:

$$
\boxed{
w=X^{1/4},
\qquad
z=X^{1/3+o(1)}.
}
$$

The half-weight:

$$
\boxed{
1/2
}
$$

is the minimal admissible coefficient within the natural two-statistic ansatz.

Standard:

$$
\theta=3/5
$$

constant audit:

$$
\boxed{
C_{\mathrm{coarse}}
\approx
0.499401183388,
}
$$

$$
\boxed{
C_{\mathrm{med}}
\approx
0.830596870470.
}
$$

Full subtraction:

$$
\boxed{
C_{\mathrm{coarse}}-C_{\mathrm{med}}
\approx
-0.331195687082
<0,
}
$$

but half-weight:

$$
\boxed{
C_{\mathrm{coarse}}
-
\frac12C_{\mathrm{med}}
\approx
0.084102748153
>0.
}
$$

Thus:

$$
\boxed{
\text{Chen-style half weighting genuinely rescues the sign}.
}
$$

However, strict pressure must still pay:

$$
\boxed{
A_P
+
\frac12A_{2,1}
+
\frac12A_{3,1},
}
$$

and the remaining normalized window is only:

$$
\boxed{
\approx0.0841.
}
$$

Therefore:

$$
\boxed{
\mathrm{HSP\ STILL\ NOT\ PROVED}.
}
$$

The actual next bottleneck has been reduced to a sharp upper ledger for:

# Prime Cost + Medium-$P_2$ Cost + Triple Cost

as displayed above.

---

# 55. Recommendation for the Next Round

# TCDC-06
## Strict-Pressure Extra-Cost Ledger / Prime–Medium–Triple Closure

The next round no longer changes the pointwise weight.

It directly handles:

$$
A_P,
\quad
A_{2,1},
\quad
A_{3,1}.
$$

### Part A — Prime Branch

$$
2m=rp+q.
$$

Establish the sharpest upper constant,

rather than using only one-dimensional BT.

### Part B — Medium-$P_2$

$$
2m=rp+\ell q,
$$

with：

$$
w<\ell\le z<q.
$$

Using:

- dyadic $\ell$；
- balanced $r,p$；
- switched $\ell q$ structure。

### Part C — Triple

$$
2m=rp+\ell q_2q_3.
$$

Perform genuine Chen switching.

### Part D — Constant Gate

Put all constants into:

$$
\boxed{
C_P
+
\frac12C_{2,1}
+
\frac12C_{3,1}
<
0.0841027\ldots
}
$$

If existing unconditional providers cannot attain this,

measure precisely:

> how far strict HSP remains from closure.

---

# Appendix A: Pointwise State Table

```yaml
coarse_domain:
  RootRough_w: true
  max_Omega: 3

states:

  prime:
    target: 0
    weight:
      <= 0

  desired_P2:
    medium_multiplicity: 0
    target: 1
    weight: 1

  medium_P2_nu1:
    target: 0
    weight: 0

  medium_P2_nu2:
    target: 0
    weight: 0

  P3_nu1:
    target: 0
    weight: 0

  P3_nu2:
    target: 0
    weight: 0

  P3_nu3:
    target: 0
    weight: -1/2
```

---

# Appendix B: Weighted Pressure Ledger

```yaml
Pi_lower:

  positive:
    A1:
      coarse_RootRough_w

  negative:

    AP:
      prime_complement
      coefficient:
        1

    A2:
      medium_prime_multiplicity
      coefficient:
        1/2

    A2_1:
      exactly_one_medium_P2
      coefficient:
        1/2

    A3_1:
      exactly_one_medium_P3
      coefficient:
        1/2
```

---

# Appendix C: Current $3/5$ Constant Audit

```yaml
theta:
  3/5

w:
  X^(1/4)

coarse_s:
  12/5

C_coarse:
  0.499401183388

C_medium_full:
  0.830596870470

C_medium_half:
  0.415298435235

full_subtraction_margin:
  -0.331195687082

half_weight_margin_before_extra_costs:
  0.084102748153
```

---

# Appendix D: Finite Calibration

```yaml
lambda:
  1.1

samples:
  pointwise_weight:
    verified: true

  weighted_total_le_actual_pressure:
    verified: true

status:
  computational_evidence_only: true
```

---

# Appendix E: Commit Decision

```yaml
research_round:
  TCDC-05

decision:

  strict_semiprime_pointwise_weight:
    proved

  half_weight_optimality:
    proved_within_selected_ansatz

  square_correction_absorbed_by_multiplicity:
    true

  half_weight_sign_rescue:
    diagnostic_positive

  strict_extra_costs:
    unresolved

  HSP_proved:
    false

  Goldbach_proved:
    false

next:
  TCDC-06_StrictPressure_ExtraCostLedger_PrimeMediumTriple_Closure
```

---

# References / Audited External Sources

1. Terence Tao, **254A, Supplement 5: The linear sieve and Chen's theorem**, 2015.

   Relevant facts:
   - classical Chen lower-weight lemma uses a $1/2$ coefficient on medium-prime divisibility together with triple-factor and square corrections;
   - Chen's target is $P_2$, so primes and semiprimes are both acceptable;
   - the proof proceeds by lower-bounding a rough term and upper-bounding medium-factor / triple-factor terms, with switching used on the difficult triple term.

2. James Maynard, **Primes in arithmetic progressions to large moduli III: Uniform residue classes**, *Memoirs of the American Mathematical Society* 306 (2025), no. 1544.

   Relevant fact:
   Proposition 5.3 treats balanced bilinear convolutions near $x^{1/2}$ under a residue compatibility condition. The high-suffix base $r,p\asymp X^{1/2}$ has the correct broad convolution shape, but no direct linear-sieve provider claim is made here.

3. Zhiyuan Yang, **Convolution-type Bombieri-Vinogradov theorem with well-factorable Weights, and its applications**, arXiv:2608.13299 (2026).

   Relevant fact:
   provides a modern convolution / well-factorable-weight template potentially relevant to medium-divisor terms. The audited statement retains fixed-residue dependence, so no direct Goldbach-shift application is asserted.

4. Classical dimension-$1$ linear sieve functions:
   $$
   F_1(s)=\frac{2e^\gamma}{s}
   $$
   for $1<s\le3$, and
   $$
   f_1(s)=\frac{2e^\gamma}{s}\log(s-1)
   $$
   for $2\le s\le4$.
