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

# SRBRD-18
## BV-Switched Row / Weighted Buchstab Constant Closure
### Fixed-Row BV No-Go, Aggregate Bilinear Switching, Near-EH Plain-Sieve Threshold and Constant Ledger

**Parent program:** RG-SCP / Reverse Goldbach Structural Closure Program  
**Branch:** SRBRD — Symmetric Root-Bounded Relation Domain  
**Round:** SRBRD-18  
**Date:** 2026-09-30  
**Version:** v0.1  
**Authors:** Neo.K; Aletheia (GPT-5.6 Sol)  
**Type:** Quantitative Constant Audit / Distribution-Level Barrier / Aggregate Bilinear Switching Interface  
**Prerequisites:** SRBRD-00 through SRBRD-17  
**Status:** Fixed-row BV + an ordinary linear sieve has been proved still insufficient at the constant level; an aggregate bilinear switched sequence and near-EH plain-sieve threshold have been established; Goldbach remains unproved

---

# 0. This Round's Sole Aim

SRBRD-17 has proved:

1. The normalized cost of a naive unswitched dimension-2 row upper bound is approximately:
   $$
   60.5588;
   $$
2. ideal SRBRD ledger：
   $$
   9-18\log(3/2)
   \approx1.70163>0;
   $$
3. A semiprime row has exact prime-cofactor switching:
   $$
   n_r
   =
   \#\left\{
   u\in\mathbb P:
   r\le u\le X/r,
   \quad
   2m-ru\text{ RootRough}_{z_3}
   \right\};
   $$
4. local Euler product exact factor：
   $$
   V_m(z)=P_0(z)W_m(z).
   $$

Thus this round must answer:

> If Bombieri–Vinogradov and an ordinary linear sieve are connected directly to a switched row, are the constants already sufficient?

The answer remains:

$$
\boxed{
\text{Insufficient.}
}
$$

Moreover, the failure can be quantified very clearly.

---

# 1. Global Scale

Let:

$$
\boxed{
X=2m-3.
}
$$

cube-root cutoff：

$$
\boxed{
z_3=X^{1/3}
}
$$

Integer rounding is ignored in the continuum diagnostic.

semiprime least factor：

$$
\boxed{
r=X^t,
\qquad
\frac13\le t\le\frac12.
}
$$

Scale of the prime-cofactor range:

$$
\boxed{
U_r
=
\frac Xr
=
X^{1-t}.
}
$$

---

# 2. Fixed-Row Prime Sequence

SRBRD-17's switched row:

$$
n_r
=
\#\left\{
u\in\mathbb P:
r\le u\le U_r,
\quad
2m-ru
\text{ RootRough}_{z_3}
\right\}.
$$

For:

$$
p\le z_3,
$$

$$
p\nmid m,
$$

one needs to avoid:

$$
\boxed{
u
\equiv
2m\,r^{-1}
\pmod p.
}
$$

Thus, among prime cofactors,

this is a dimension-1 upper sieve.

---

# 3. Ordinary Bombieri–Vinogradov Level on One Fixed Row

For a prime sequence of size:

$$
U_r
$$

as displayed above,

ordinary Bombieri–Vinogradov gives the natural average modulus level:

$$
\boxed{
D_r
=
U_r^{1/2}
(\log U_r)^{-B}
}
$$

up to logarithmic loss.

continuum exponent：

$$
\boxed{
D_r
\approx
X^{(1-t)/2}.
}
$$

---

# 4. Full Cube-Root Cutoff Is Beyond the Fixed-Row BV Level

Since:

$$
z_3=X^{1/3},
$$

while, for:

$$
t>\frac13,
$$

$$
\frac{1-t}{2}
<
\frac13.
$$

Thus:

## Diagnostic SRBRD-18-D01

$$
\boxed{
D_r<z_3
\quad
\text{for every interior row }
t>\frac13.
}
$$

That is:

> Ordinary fixed-row Bombieri–Vinogradov cannot directly sift the linear sieve to the full cube-root cutoff.

---

# 5. Partial Linear-Sieve Cutoff

Let the linear sieve parameter be:

$$
s>1.
$$

Take:

$$
\boxed{
w_r
=
D_r^{1/s}.
}
$$

continuum exponent：

$$
\boxed{
w_r
\approx
X^{(1-t)/(2s)}.
}
$$

Since:

$$
s>1,
$$

within the row band:

$$
w_r\le z_3.
$$

Thus:

> We can only sieve to $w_r$ first,
> and then treat the missing small-prime band:
> $$
> (w_r,z_3]
> $$
> as a loss.

---

# 6. Exact Missing-Band Penalty

SRBRD-17's opposite-endpoint factor:

$$
W_m(z)
=
\prod_{\substack{
3\le p\le z\\
p\nmid m
}}
\left(
1-\frac1{p-1}
\right).
$$

Define the exact partial/full ratio:

$$
\boxed{
\Psi_m(w,z_3)
=
\frac{
W_m(w)
}{
W_m(z_3)
}
}
$$

$$
=
\prod_{\substack{
w<p\le z_3\\
p\nmid m
}}
\frac{p-1}{p-2}.
$$

Clearly:

$$
\boxed{
\Psi_m(w,z_3)\ge1.
}
$$

---

# 7. Generic Mertens-Scale Missing-Band Ratio

For the generic model with no additional center-divisor bonus,

the dimension-1 product satisfies:

$$
W_0(z)
\asymp
\frac{C}{\log z}.
$$

Therefore:

$$
\boxed{
\Psi_0(w_r,z_3)
\sim
\frac{
\log z_3
}{
\log w_r
}.
}
$$

Substituting:

$$
\log z_3
\sim
\frac13\log X,
$$

$$
\log w_r
\sim
\frac{1-t}{2s}\log X,
$$

we obtain:

## Diagnostic SRBRD-18-D02

$$
\boxed{
\Psi_0
\sim
\frac{
2s
}{
3(1-t)
}.
}
$$

---

# 8. Linear Sieve Upper Function

classical linear sieve upper function：

$$
F_1(s)
$$

satisfying:

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

For:

$$
1<s\le3.
$$

More generally:

$$
\boxed{
\frac{d}{ds}
\left(
sF_1(s)
\right)
=
f_1(s-1)
\ge0.
}
$$

Therefore:

## External Sieve Fact

$$
\boxed{
sF_1(s)
\ge
2e^\gamma
\qquad
(s>1).
}
$$

---

# 9. Optimally Tuned Fixed-Row BV Multiplier

partial sieve upper relative to full ideal density：

$$
\boxed{
R_{\mathrm{fixBV}}(t,s)
=
F_1(s)
\Psi_0(w_r,z_3).
}
$$

From D02:

$$
R_{\mathrm{fixBV}}
\sim
F_1(s)
\frac{2s}{3(1-t)}.
$$

Also:

$$
sF_1(s)\ge2e^\gamma.
$$

Thus:

## Diagnostic SRBRD-18-D03

$$
\boxed{
R_{\mathrm{fixBV}}(t,s)
\ge
\frac{
4e^\gamma
}{
3(1-t)
}.
}
$$

For:

$$
1<s\le3,
$$

this lower envelope actually attains equality in the continuum model.

Thus:

$$
\boxed{
\text{Tuning }s\text{ cannot resolve the fixed-row BV constant problem.}
}
$$

---

# 10. Fixed-Row BV Aggregate Row Cost

SRBRD-17's ideal double-row cost:

$$
18
\int_{1/3}^{1/2}
\frac{dt}{t}.
$$

Multiply by D03's minimum fixed-row multiplier:

$$
\boxed{
C_{\mathrm{row}}^{\mathrm{fixBV}}
=
18
\int_{1/3}^{1/2}
\frac{
4e^\gamma
}{
3(1-t)
}
\frac{dt}{t}.
}
$$

Thus:

$$
=
24e^\gamma
\int_{1/3}^{1/2}
\frac{
dt
}{
t(1-t)
}.
$$

---

# 11. Exact Fixed-Row Integral

$$
\int_{1/3}^{1/2}
\frac{
dt
}{
t(1-t)
}
=
\boxed{
\log2.
}
$$

Therefore:

## Diagnostic SRBRD-18-D04

$$
\boxed{
C_{\mathrm{row}}^{\mathrm{fixBV}}
=
24e^\gamma\log2
\approx
29.6290878.
}
$$

---

# 12. Improvement over Unswitched DHR

SRBRD-17：

$$
C_{\mathrm{row}}^{\mathrm{unswitched}}
\approx60.5588.
$$

Now:

$$
\boxed{
60.56
\to
29.63.
}
$$

Thus switching genuinely removes about half the constant inflation.

However:

$$
\boxed{
29.63>9.
}
$$

But it remains impossible to complete the ideal ledger crossing using only:

> fixed-row BV + ordinary linear upper sieve

as displayed above.

---

# 13. Fixed-Row BV No-Go

Even if:

- coarse lower；
- Buchstab shell upper；

are both idealized to the best possible local-density constants,

they leave only:

$$
\boxed{
9.
}
$$

But the fixed-row BV row already costs at least:

$$
\boxed{
29.63.
}
$$

Thus, with zero transport, the ledger is at most:

$$
\boxed{
9-29.63
\approx
-20.63.
}
$$

This is the:

# Fixed-Row BV Constant No-Go

It is not a theorem that Goldbach is impossible,

but only a quantitative rejection of this specific provider architecture.

---

# 14. Full-Cutoff Aggregate Distribution Model

Now consider the stronger hypothetical / provider interface:

> Instead of using BV row by row,
> obtain a distribution exponent directly for the entire switched bilinear sequence:
> $$
> \theta.
> $$

That is, the aggregate bilinear sequence can be controlled for moduli up to:

$$
\boxed{
D=X^\theta
}
$$

as displayed above.

At the full cutoff:

$$
z_3=X^{1/3},
$$

linear sieve parameter：

$$
\boxed{
s=3\theta.
}
$$

---

# 15. Plain Linear-Sieve Aggregate Multiplier

If:

$$
1<s\le3,
$$

that is:

$$
\frac13<\theta\le1,
$$

then:

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

Thus, relative to the ideal switched row:

$$
\boxed{
R_{\mathrm{agg}}(\theta)
=
\frac{
2e^\gamma
}{
3\theta
}.
}
$$

---

# 16. Aggregate Plain-Sieve Row Cost

ideal row cost：

$$
18\log\frac32.
$$

Thus:

## Diagnostic SRBRD-18-D05

$$
\boxed{
C_{\mathrm{row}}^{\mathrm{agg}}(\theta)
=
\frac{
12e^\gamma
\log(3/2)
}{
\theta
}.
}
$$

---

# 17. Ordinary Bombieri–Vinogradov Still Fails Even Aggregately

If:

$$
\theta=\frac12,
$$

then:

$$
s=\frac32,
$$

$$
F_1(3/2)
=
\frac{
4e^\gamma
}{3}
\approx2.37476.
$$

row cost：

$$
\boxed{
C_{\mathrm{row}}^{\mathrm{agg}}(1/2)
\approx
17.33191.
}
$$

Thus:

$$
\boxed{
17.33>9.
}
$$

Even if the aggregate sequence can fully use the BV level:

$$
1/2
$$

to sift to:

$$
z_3,
$$

the plain linear upper bound is still insufficient.

---

# 18. Plain-Sieve Distribution Threshold

With zero transport and ideal coarse/shell contributions, one needs:

$$
C_{\mathrm{row}}^{agg}(\theta)<9.
$$

That is:

$$
\frac{
12e^\gamma\log(3/2)
}{
\theta
}
<9.
$$

Thus:

## Diagnostic SRBRD-18-D06

$$
\boxed{
\theta
>
\theta_*
=
\frac{
12e^\gamma\log(3/2)
}{9}
}
$$

$$
\boxed{
\theta_*
\approx
0.9628836273.
}
$$

That is:

> **Using only a plain linear upper sieve + the distribution level,
> a level almost equal to 1 is needed.**

---

# 19. Near Elliott–Halberstam Interpretation

Bombieri–Vinogradov：

$$
\theta=\frac12.
$$

The ideal direction of the Elliott–Halberstam conjecture:

$$
\theta<1.
$$

T18 shows:

$$
\boxed{
\theta_*\approx0.963.
}
$$

Thus the plain-sieve crossing threshold is very close to:

# Elliott–Halberstam Level

This again proves:

$$
\boxed{
\text{Increasing the level of distribution alone is not a practical unconditional solution.}
}
$$

---

# 20. Current Structured-Weight Exponents as a Diagnostic

The following is only an external comparison;

the weight hypotheses differ between theorems,

so they cannot be directly inserted into the SRBRD sequence without checking the hypotheses.

### Bombieri–Friedlander–Iwaniec style

well-factorable：

$$
\theta=\frac47.
$$

### Maynard well-factorable

The published result can reach:

$$
\theta=\frac35-\varepsilon.
$$

### stronger structured-weight literature

Certain more specialized weights can reach:

$$
\theta=\frac58
$$

or nearby or higher levels.

---

# 21. Plain Linear-Sieve Costs at Selected Exponents

Use D05 solely as a constant diagnostic:

| $\theta$ | $s=3\theta$ | $F_1(s)$ | row cost |
|---:|---:|---:|---:|
| $1/2$ | $1.5$ | $2.37476$ | $17.3319$ |
| $4/7$ | $12/7$ | $2.07792$ | $15.1654$ |
| $3/5$ | $1.8$ | $1.97897$ | $14.4433$ |
| $5/8$ | $1.875$ | $1.89981$ | $13.8655$ |
| $1$ | $3$ | $1.18738$ | $8.66595$ |

Even with:

$$
\theta=\frac58,
$$

the plain row cost remains:

$$
\boxed{
13.87>9.
}
$$

---

# 22. Consequence

Thus SRBRD-18 reaches a strong architectural conclusion:

$$
\boxed{
\text{We cannot pursue only a higher distribution exponent.}
}
$$

One must also use:

- weighted Buchstab subtraction；
- switching identities；
- transport overlap；
- possibly well-factorable / bilinear structure；

to change the ledger itself.

---

# 23. Required Effective Row Multiplier

Write the aggregate row cost as:

$$
\boxed{
18\log\frac32
\cdot
\overline R.
}
$$

With zero transport and ideal coarse/shell contributions, one needs:

$$
18\log\frac32
\cdot
\overline R
<9.
$$

Thus:

## Diagnostic SRBRD-18-D07

$$
\boxed{
\overline R
<
\frac{
9
}{
18\log(3/2)
}
}
$$

$$
\boxed{
\overline R
<
1.2331517312.
}
$$

This is currently the most intuitive row-constant target.

---

# 24. Transport-Adjusted Threshold

If the normalized transport gain is:

$$
\Phi\ge0,
$$

and the available coarse-shell budget is:

$$
B_{CS},
$$

then the row multiplier needs only:

$$
\boxed{
\overline R
<
\frac{
B_{CS}+\Phi
}{
18\log(3/2)
}.
}
$$

ideal：

$$
B_{CS}=9.
$$

Thus transport relaxes the:

$$
1.23315
$$

threshold.

But finite evidence shows that:

$$
\Phi
$$

is usually an order-one correction,

not a huge compensation sufficient to absorb:

$$
29.63
$$

or:

$$
60.56
$$

as displayed above.

---

# 25. Finite Effective-Row Calibration

SRBRD-17's finite calibration:

$$
U_{SP}^{one}
W_m(z_3)
$$

is the ideal switched main term.

Define the observed multiplier:

$$
\boxed{
R_{\mathrm{obs}}
=
\frac{
n_{SP}
}{
U_{SP}^{one}
W_m(z_3)
}.
}
$$

selected：

| $m$ | $R_{\mathrm{obs}}$ |
|---:|---:|
| $1000$ | $1.18393$ |
| $5000$ | $1.02128$ |
| $10000$ | $0.98007$ |
| $100000$ | $1.00355$ |

All are below the zero-transport target:

$$
1.23315.
$$

This is only computational evidence,

but indicates:

$$
\boxed{
\text{The actual arithmetic row constant seems close to }1,
}
$$

rather than the classical fixed-row sieve's:

$$
3\text{--}5
$$

or even larger values.

---

# 26. Aggregate Bilinear Switched Sequence

Now define the object that should actually be estimated as a whole.

The row bulk requires:

$$
2m-ru\ge z_3^2.
$$

Define the prime-pair parameter set:

$$
\boxed{
\mathcal P_m
=
\left\{
(r,u):
r,u\in\mathbb P,
\quad
z_3<r\le u,
\quad
ru\le2m-z_3^2
\right\}.
}
$$

For the pair:

$$
(r,u),
$$

define the residual value:

$$
\boxed{
a_{r,u}
=
2m-ru.
}
$$

---

# 27. Bulk Semiprime Mass as a Sifted Bilinear Sequence

## Theorem SRBRD-18-T01

$$
\boxed{
n_{SP}^{bulk}
=
\#
\left\{
(r,u)\in\mathcal P_m:
\operatorname{RootRough}_{z_3}(a_{r,u})
\right\}.
}
$$

Since:

$$
a_{r,u}\ge z_3^2,
$$

RootRough here is equivalent to:

$$
\boxed{
\gcd
\left(
a_{r,u},
P(z_3)
\right)
=1
}
$$

where:

$$
P(z_3)
=
\prod_{\substack{
p\in\mathbb P\\
3\le p\le z_3
}}
p.
$$

---

# 28. Aggregate Local Density

Fix an odd prime:

$$
p\le z_3.
$$

Since:

$$
r,u>z_3,
$$

Thus:

$$
r,u
$$

are both units modulo:

$$
p
$$

as displayed above.

bad condition：

$$
p\mid2m-ru.
$$

---

# 29. Center Divisor

If:

$$
p\mid m,
$$

then the bad congruence is:

$$
ru\equiv0\pmod p.
$$

However:

$$
r,u
$$

are units.

Thus:

## Theorem SRBRD-18-T02

$$
\boxed{
p\mid m
\Longrightarrow
\text{aggregate bad local density}=0.
}
$$

---

# 30. Noncenter Prime

If:

$$
p\nmid m,
$$

For each nonzero:

$$
r\bmod p,
$$

there exists a unique:

$$
u
\equiv
2m\,r^{-1}
\pmod p.
$$

In:

$$
(p-1)^2
$$

unit pairs,

the number of bad pairs is:

$$
p-1.
$$

Thus:

## Theorem SRBRD-18-T03

$$
\boxed{
g_m(p)
=
\frac1{p-1}
}
$$

for：

$$
p\nmid m.
$$

This agrees exactly with SRBRD-17's:

$$
W_m
$$

as displayed above.

---

# 31. Squarefree Aggregate Density

For squarefree odd:

$$
d
$$

whose prime factors are all:

$$
\le z_3,
$$

If:

$$
(d,m)=1,
$$

CRT gives:

$$
\boxed{
g_m(d)
=
\frac1{\varphi(d)}.
}
$$

If:

$$
(d,m)>1,
$$

then:

$$
\boxed{
g_m(d)=0
}
$$

for the simultaneous divisibility event containing a center-divisor prime.

This is the exact local-density law of the aggregate bilinear sequence.

---

# 32. Aggregate Distribution Remainder

Let:

$$
A_d^{bil}
=
\#
\left\{
(r,u)\in\mathcal P_m:
d\mid2m-ru
\right\}.
$$

Define:

$$
\boxed{
R_d^{bil}
=
A_d^{bil}
-
g_m(d)
|\mathcal P_m|.
}
$$

The actual analytic question is:

$$
\boxed{
\text{For how large a }D
\text{ can the average of }
R_d^{bil}
\text{ be controlled?}
}
$$

rather than controlling the prime row by row:

$$
u.
$$

---

# 33. Bilinear Distribution Provider

It is recommended to define formally:

$$
\boxed{
\operatorname{BilDist}(\theta,A)
}
$$

means:

for appropriate sieve weights:

$$
\lambda_d,
$$

support：

$$
d\le X^\theta,
$$

we have:

$$
\boxed{
\sum_{d\le X^\theta}
\lambda_d
R_d^{bil}
\ll
\frac{
|\mathcal P_m|
}{
(\log X)^A
}.
}
$$

The exact admissible weight class must be specified in a future formal theorem.

---

# 34. Ordinary BV Does Not Automatically Give BilDist

Bombieri–Vinogradov directly controls:

> Primes in one arithmetic-progression variable.

Here:

$$
A_d^{bil}
$$

is the:

$$
\boxed{
\text{prime} \times \text{prime}
}
$$

multiplicative-convolution congruence:

$$
ru\equiv2m\pmod d.
$$

Thus:

$$
\boxed{
\text{The ordinary BV theorem itself is not BilDist}.
}
$$

One needs:

- bilinear form estimates；
- convolution-type BV；
- dispersion；
- well-factorable weights；
- or a switching decomposition。

---

# 35. Current Literature Interface

Modern distribution literature does include:

- well-factorable prime AP estimates beyond exponent $1/2$；
- convolution-type Bombieri–Vinogradov estimates；
- bilinear / trilinear structured moduli results。

But each theorem has very specific:

- coefficient factorability；
- support ranges；
- modulus factorization；
- variable-length hypotheses。

Thus:

$$
\boxed{
\text{One cannot insert an exponent directly into SRBRD merely after seeing it}.
}
$$

SRBRD-19 must perform a hypothesis match item by item.

---

# 36. Even Full BV-Scale BilDist Is Not Enough with Plain Linear Sieve

Suppose, very optimistically, that:

$$
\operatorname{BilDist}(\theta=1/2)
$$

holds,

and that a plain linear upper sieve can be used directly at the full cutoff:

$$
z_3
$$

as displayed above.

T17 has proved:

$$
C_{\mathrm{row}}
\approx17.33>9.
$$

Thus:

$$
\boxed{
\text{BilDist}(1/2)
+
\text{plain linear sieve}
}
$$

is still insufficient.

---

# 37. Even Known Beyond-$1/2$ Structured Exponents Are Not Sufficient by Themselves

pure constant diagnostic：

- 
  $$
  \theta=4/7
  $$
  row cost：
  $$
  \approx15.17;
  $$
- 
  $$
  \theta=3/5
  $$
  row cost：
  $$
  \approx14.44;
  $$
- 
  $$
  \theta=5/8
  $$
  row cost：
  $$
  \approx13.87.
  $$

All are:

$$
\boxed{
>9.
}
$$

Thus the actual breakthrough must change the:

$$
\boxed{
\text{weighted ledger}
}
$$

rather than merely increasing:

$$
\theta.
$$

---

# 38. Weighted Buchstab Is Therefore Mandatory

The SRBRD-16 master identity currently penalizes semiprime rows by:

$$
-2n_{SP}
$$

as displayed above.

But the cost of all semiprime states to failure coverage need not have weight:

$$
2.
$$

Since:

- $SS$ states later have the following added back:
  $$
  M_{SS};
  $$
- Center rows have forced internal flow;
- Distinct factor ranges may have different contamination efficiencies;
- Buchstab shells and rows have structural overlap.

Thus one should introduce a:

# Weighted Semiprime Penalty

---

# 39. Abstract Weighted Row Functional

Choose a weight function:

$$
\boxed{
0\le w(r)\le2.
}
$$

Decompose:

$$
2\sum_r n_r
$$

into:

$$
\boxed{
\sum_r
w(r)n_r
+
\mathcal R_w,
}
$$

where the residual:

$$
\mathcal R_w
$$

is compensated by a transport / overlap certificate.

Target:

> Apply the analytic row upper bound only to the lower-weight part,
> then pay the remaining penalty with arithmetic transport.

This is a natural version of Chen's weighted-sieve philosophy in the language of SRBRD transport.

---

# 40. Exact Transport Reweighting Interface

From:

$$
M_{PP}
=
|\widehat{\mathcal S}_{z_3}|
-
2n_{SP}
+
M_{SS},
$$

If one can prove:

$$
\boxed{
M_{SS}
\ge
\sum_r
(2-w(r))n_r
-
E_w,
}
$$

then:

$$
\boxed{
M_{PP}
\ge
|\widehat{\mathcal S}_{z_3}|
-
\sum_rw(r)n_r
-
E_w.
}
$$

then the weighted row penalty is not an arbitrary heuristic.

It can be rigorously justified by a forced transport lower bound.

---

# 41. Weighted Buchstab / Transport Closure

Combining the coarse cutoff:

$$
|\widehat{\mathcal S}_{z_3}|
=
|\widehat{\mathcal S}_y|
-
\sum_{y<r\le z_3}
|\mathcal B_r^{pair}|,
$$

we obtain:

## Theorem SRBRD-18-T04

If we have:

$$
M_{SS}
\ge
\sum_{r>z_3}
(2-w(r))n_r
-
E_w,
$$

then:

$$
\boxed{
M_{PP}
\ge
|\widehat{\mathcal S}_y|
-
\sum_{y<r\le z_3}
|\mathcal B_r^{pair}|
-
\sum_{r>z_3}
w(r)n_r
-
E_w.
}
$$

This is the:

# Weighted Buchstab–Transport Identity

---

# 42. Why T04 Matters

The plain ledger requires the effective row multiplier:

$$
<1.233.
$$

If transport can validly lower the average row weight:

$$
2
$$

as displayed above,

the required quality of the analytic row upper bound is greatly relaxed.

Thus:

$$
\boxed{
\text{Transport is not only an additive bonus,
but can also redefine the contamination weight.}
}
$$

This may be better suited to quantitative optimization than merely:

$$
+L_{SS}
$$

as displayed above.

---

# 43. Transport Weight from Center-Divisor Rows

SRBRD-15：

If:

$$
r\mid m,
$$

then:

$$
M_{r,0}\le1.
$$

Thus, for row:

$$
r
$$

most of its mass is internal.

For large:

$$
n_r,
$$

the effective contamination weight is close to:

$$
\boxed{
1
}
$$

rather than:

$$
2.
$$

For an $SS$ ordered pair causes, in:

$$
2n_{SP}-M_{SS}
$$

a net penalty of only:

$$
1
$$

per semiprime endpoint-pair contribution.

This provides an explicit source of weight reduction.

---

# 44. Cross-Row Transport Can Lower Weight Too

SRBRD-15 row/block deficiency：

$$
M_{SS}
\ge L_{SS}^{row/block}.
$$

Any such lower bound can be converted to:

$$
w(r)
$$

or block weights.

Thus future constant optimization can become a joint linear program of:

$$
\boxed{
\text{analytic upper cost}
+
\text{transport discount}
}
$$

as displayed above.

---

# 45. Quantitative Constant Ledger

Define the normalized quantities:

$$
\boxed{
C_L
}
$$

= Coarse lower contribution,

$$
\boxed{
C_B
}
$$

= Buchstab band upper loss,

$$
\boxed{
C_R
}
$$

= Weighted switched row upper cost,

$$
\boxed{
C_T
}
$$

= Transport correction.

global gate：

$$
\boxed{
C_L-C_B-C_R+C_T>0.
}
$$

---

# 46. Ledger Levels

Currently:

### Ideal local density

$$
C_L-C_B=9.
$$

### Ideal unweighted row

$$
C_R
=
18\log(3/2)
\approx7.298.
$$

### Ideal zero-transport margin

$$
\boxed{
1.7016.
}
$$

### Fixed-row BV switched row

$$
C_R
\ge29.629.
$$

### Aggregate BV plain linear

$$
C_R
\approx17.332.
$$

### Needed target

roughly：

$$
\boxed{
C_R-C_T<9.
}
$$

---

# 47. Transport Calibration in Normalized Units

This is only a finite heuristic calibration.

Use:

$$
H V_m(z_3)
$$

as the cube-boundary density scale,

and the corresponding dimension-2 continuum factor is approximately:

$$
9.
$$

Define:

$$
\boxed{
\Phi_{\mathrm{obs}}
=
9
\frac{
M_{SS}
}{
H V_m(z_3)
}.
}
$$

selected：

- $m=1000$:
  Approximately:
  $$
  0.55;
  $$
- $m=5000$:
  Approximately:
  $$
  0.59;
  $$
- $m=10000$:
  Approximately:
  $$
  0.85;
  $$
- $m=100000$:
  Approximately:
  $$
  0.96.
  $$

This is still far from sufficient, by itself, to repair:

$$
17.33
$$

or:

$$
29.63.
$$

Thus:

$$
\boxed{
\text{Weighted shell/row constant reduction is still necessary.}
}
$$

---

# 48. Distribution Exponent with Transport

If only the plain linear row multiplier is used,

the normalized transport gain:

$$
\Phi
$$

changes the threshold to:

$$
\boxed{
\theta
>
\frac{
12e^\gamma\log(3/2)
}{
9+\Phi
}
}
$$

In:

$$
\Phi\approx1
$$

the scale remains approximately:

$$
\boxed{
0.8666
}
$$

as displayed above.

This remains far higher than standard BV and current general structured-weight results.

Thus transport alone also cannot replace a weighted sieve.

---

# 49. Three Different Mean-Value Problems

In subsequent work, the following must not be confused:

## Problem A — Prime AP

ordinary BV：

$$
p\equiv a\pmod q.
$$

## Problem B — Bilinear Product AP

SRBRD aggregate rows：

$$
ru\equiv2m\pmod q.
$$

## Problem C — Weighted Buchstab Bilinear AP

Add:

- $r$ range weights；
- Buchstab coefficients；
- transport weights。

What SRBRD-19 actually needs is:

$$
\boxed{
\text{Problem C}.
}
$$

not merely citing Problem A's exponent.

---

# 50. Current 2026 Convolution Literature

New convolution-type Bombieri–Vinogradov / well-factorable-weight results already exist in 2026.

These types of theorems and SRBRD Problem B/C are conceptually closer to ordinary BV.

However:

$$
\boxed{
\text{Hypothesis-to-hypothesis matching has not yet been done,
so this document does not treat them as providers.}
}
$$

The next round should check, theorem by theorem:

- variables support；
- coefficient bounds；
- well-factorability；
- modulus range；
- fixed residue dependence；
- endpoint truncation。

---

# 51. Formal Theorem Queue

```yaml
SRBRD_18:
  T01: bulk_semiprime_mass_as_sifted_bilinear_prime_pair_sequence
  T02: center_prime_gives_zero_local_bad_density
  T03: noncenter_prime_aggregate_local_density_one_over_p_minus_one
  T04: weighted_Buchstab_transport_identity
```

---

# 52. Quantitative Diagnostic Queue

```yaml
SRBRD_18_Diagnostics:
  D01:
    fixed_row_BV_level_below_cube_cutoff

  D02:
    generic_missing_band_ratio

  D03:
    fixed_row_effective_multiplier_lower_envelope

  D04:
    fixed_row_BV_aggregate_cost:
      24*exp(gamma)*log(2)

  D05:
    aggregate_plain_sieve_row_cost:
      12*exp(gamma)*log(3/2)/theta

  D06:
    zero_transport_distribution_threshold:
      theta_star:
        approx: 0.9628836273

  D07:
    zero_transport_effective_row_multiplier_target:
      approx: 1.2331517312
```

---

# 53. Acceptance Gate

Before SRBRD-18 can enter a formal / publication core, it requires:

1. fixed-row BV level derivation；
2. partial cutoff definition；
3. exact missing-band ratio；
4. Mertens-scale ratio clearly marked asymptotic；
5. linear sieve $F_1$ formula sourced；
6. $sF(s)$ monotonic theorem sourced；
7. fixed-row cost integral；
8. aggregate $\theta$-model clearly marked provider diagnostic；
9. distribution exponent table marked non-applicative comparison；
10. aggregate bilinear local-density theorem；
11. bilinear remainder definition；
12. ordinary BV ≠ BilDist firewall；
13. weighted transport identity；
14. finite calibration separated from rigorous bounds；
15. no current-literature theorem silently assumed applicable；
16. No Goldbach proof claim.

---

# 54. Verdict

This round can formally give:

$$
\boxed{
\mathrm{SRBRD\mbox{-}18\ DISTRIBUTION\mbox{-}LEVEL\ BARRIER\ PASS}.
}
$$

The most important negative theorem-level diagnosis:

$$
\boxed{
\text{fixed-row BV + ordinary linear sieve
cannot provide the required row constant.}
}
$$

continuum lower envelope：

$$
\boxed{
C_{\mathrm{row}}^{fixBV}
\approx29.63>9.
}
$$

More strongly,

even assuming that the aggregate plain linear sieve directly has a distribution exponent:

$$
\theta,
$$

zero-transport crossing still requires:

$$
\boxed{
\theta>0.96288\ldots
}
$$

Thus:

$$
\boxed{
\text{distribution level alone is not the missing ingredient.}
}
$$

The actual remaining target is:

$$
\boxed{
\text{weighted Buchstab}
+
\text{aggregate bilinear distribution}
+
\text{transport discount}.
}
$$

The exact positive structural result is:

$$
\boxed{
g_m(p)
=
\begin{cases}
0,&p\mid m,\\
1/(p-1),&p\nmid m,
\end{cases}
}
$$

for aggregate prime-pair switched rows，

showing that the aggregate switched sequence is genuinely a dimension-1 bilinear sieve object.

However:

$$
\boxed{
\mathrm{UNIFORM\ CONSTANT\ CROSSING\ STILL\ OPEN}.
}
$$

and:

$$
\boxed{
\mathrm{GOLDBACH\ STILL\ OPEN}.
}
$$

---

# 55. Recommendations for the Next Round

# SRBRD-19
## Convolution-BV Hypothesis Match / Weighted Transport Ledger

The next round no longer invents new objects itself.

Directly perform external theorem matching:

1. 2025 Maynard well-factorable AP：
   $$
   3/5-\varepsilon;
   $$
2. BFI：
   $$
   4/7-\varepsilon;
   $$
3. newer bilinear / trilinear / convolution-type BV results；
4. Chen linear-sieve switching framework。

Check item by item whether the SRBRD weighted bilinear sequence satisfies:

- coefficient factorability；
- dyadic support；
- fixed-shift condition；
- modulus factorization；
- well-factorable sieve weights；
- allowable exponent。

Then establish an actual:

# Constant Ledger v1

If, after all known unconditional providers have been inserted, we still have:

$$
\boxed{
C_L-C_B-C_R+C_T\le0,
}
$$

then formally establish:

> The size of the gap in existing sieve technology.

If, unexpectedly:

$$
>0,
$$

only then enter a complete rigorous proof audit.

---

# Appendix A: Fixed-Row BV Constant Ledger

```yaml
row_band:
  t:
    min: 1/3
    max: 1/2

cofactor_size:
  U_r:
    X^(1-t)

ordinary_BV_level:
  D_r:
    approximately:
      U_r^(1/2)

partial_linear_cutoff:
  w_r:
    D_r^(1/s)

generic_missing_band_penalty:
  approximately:
    2s/(3*(1-t))

linear_sieve:
  sF_s:
    >= 2*exp(gamma)

effective_multiplier:
  >=:
    4*exp(gamma)/(3*(1-t))

aggregate_double_row_cost:
  exact_diagnostic:
    24*exp(gamma)*log(2)

decimal:
  29.6290877977
```

---

# Appendix B: Aggregate Plain-Sieve Threshold

```yaml
full_cube_cutoff:
  z3:
    X^(1/3)

distribution_exponent:
  D:
    X^theta

linear_sieve_parameter:
  s:
    3*theta

plain_row_cost:
  12*exp(gamma)*log(3/2)/theta

zero_transport_crossing:
  requires:
    theta:
      >
      0.9628836273
```

---

# Appendix C: Selected Exponent Diagnostic

| exponent $\theta$ | provenance class | plain row cost | below ideal budget 9? |
|---:|---|---:|:---|
| $1/2$ | Bombieri–Vinogradov | $17.3319$ | no |
| $4/7$ | BFI well-factorable | $15.1654$ | no |
| $3/5$ | Maynard well-factorable | $14.4433$ | no |
| $5/8$ | stronger structured-weight scale | $13.8655$ | no |
| $1$ | EH-level ideal endpoint | $8.66595$ | yes |

**Note:**
Different distribution theorems have different weight hypotheses.
This table compares only the constant effect of exponents in the plain linear-sieve model,
and does not mean the corresponding theorems can be applied directly to SRBRD.

---

# Appendix D: Aggregate Bilinear Sequence Contract

```yaml
prime_pair_parameters:
  r:
    prime
    r > z3
  u:
    prime
    u >= r
  product:
    r*u <= 2m-z3^2

residual:
  a_r_u:
    2m-r*u

bulk_semiprime_mass:
  sift:
    a_r_u:
      RootRough_z3

local_bad_density:
  p_divides_m:
    0
  p_not_divides_m:
    1/(p-1)

squarefree_density:
  if_gcd(d,m)==1:
    1/phi(d)
```

---

# Appendix E: Finite Row-Multiplier Calibration

| $m$ | exact $n_{SP}$ | ideal switched main term | observed multiplier |
|---:|---:|---:|---:|
| $1000$ | $35$ | $29.5625$ | $1.18393$ |
| $5000$ | $152$ | $148.8330$ | $1.02128$ |
| $10000$ | $291$ | $296.9190$ | $0.98007$ |
| $100000$ | $2100$ | $2092.5710$ | $1.00355$ |

zero-transport target：

$$
\boxed{
\overline R<1.2331517312.
}
$$

The selected exact data all fall within the target.

---

# Appendix F: Commit Decision

```yaml
research_round: SRBRD-18

decision:
  fixed_row_BV_no_go: true
  aggregate_plain_sieve_near_EH_threshold: true
  bilinear_switched_local_density: true
  weighted_transport_identity: true
  current_distribution_exponents_alone_insufficient: true
  uniform_constant_crossing: false
  goldbach_proved: false

main_gap:
  weighted_bilinear_distribution_plus_transport_constant

next:
  SRBRD-19_ConvolutionBV_HypothesisMatch_WeightedTransport_Ledger
```

---

# References

1. T. Tao, “254A, Supplement 5: The linear sieve and Chen’s theorem,” 2015.  
   Linear-sieve functions satisfy:
   $$
   F(s)=2e^\gamma/s
   $$
   for:
   $$
   1<s\le3,
   $$
   and:
   $$
   \frac{d}{ds}(sF(s))=f(s-1).
   $$

2. Bombieri–Vinogradov theorem. Standard mean distribution of primes in arithmetic progressions up to:
   $$
   x^{1/2}
   $$
   modulo logarithmic loss.

3. J. Maynard, “Primes in arithmetic progressions to large moduli II: well-factorable estimates,” *Memoirs of the AMS* 306 (2025), no. 1543.  
   Well-factorable weighted estimates to:
   $$
   x^{3/5-\varepsilon}.
   $$

4. Bombieri–Friedlander–Iwaniec, well-factorable prime-progressions technology up to:
   $$
   x^{4/7-\varepsilon}.
   $$

5. Z. Yang, “Convolution-type Bombieri–Vinogradov theorem with well-factorable weights, and its applications,” arXiv:2608.13299 (2026).  
   Mentioned only as a possible future convolution-interface source; no hypothesis match is asserted here.

6. Elliott–Halberstam conjecture. Used only as a scale comparison for distribution exponent near:
   $$
   1.
   $$
