Submitted:
12 March 2026
Posted:
16 March 2026
Read the latest preprint version here
Abstract
For a prime p>2, let N(p):=#{{q,r}⊂P:q≤r, q+r=p+1}, counting Goldbach representations of p+1 when p is itself prime. We study the arithmetic, computational, and heuristic behaviour of N(p) on the shifted-prime subsequence {p+1:p∈P}.Our principal result proves that the Euler product S_∞ := ∏_(l>2,l∈P)^( 1+1/((l-1)(l-2)))=1.74273… converges absolutely and equals the limiting Cesàro mean of the Hardy–Littlewood singular factor S(p+1) on this subsequence. This value, strictly greater than 1, reflects a divisibility bias from Dirichlet’s theorem and explains why the empirical constant differs structurally from 2C_2.We verify N(p)≥2 for every prime 11<p<10^7 (664 574 primes, zero violations) and classify primes into Mirror, Anchor-3, and Orphan types, proving two congruence theorems. Law 3 achieves RMSE 13 times smaller than the classical formula. Five disjoint ranges support α_∞=1/S_∞≈0.5738 over the alternative α_∞=1/2.
Keywords:
Goldbach conjecture
; shifted primes
; singular factor
; Hardy-Littlewood
; Euler product
; computational verification
1. Introduction
1.1. The Shifted-Prime Goldbach Problem
Let be a prime. We study representations equivalently , a Goldbach decomposition of with prime. All three of must be simultaneously prime — absent from classical Goldbach. This defines
1.2. Relation to Prior Work
1.3. What this Paper Does
- A prime taxonomy (Mirror, Anchor-3, Orphan) with two congruence theorems.
- Computational verification: for all primes .
- Proof that the Cesàro mean of converges to .
- Three prediction laws compared; five-range convergence table for .
1.4. Status of the Main Claims
Proved: congruence theorems, absolute convergence of , finite-truncation average formula. Computationally verified: for . Conjectural: asymptotic multiplicity, prediction laws, .
2. Definitions and Taxonomy
Definition 2.1 (Mirror prime).
is Mirror if , i.e. .
Definition 2.2 (Anchor-3 prime).
is Anchor-3 if , i.e. .
Definition 2.3 (Orphan prime).
is Orphan if neither Mirror nor Anchor-3.
Table 1 gives the taxonomy for the first 13 primes .
Table 1.
Taxonomy, decompositions, and
| Class | |||||
|---|---|---|---|---|---|
| 5 | 6 | 1 | M | 2.000 | |
| 7 | 8 | 1 | M | 1.000 | |
| 11 | 12 | 1 | A | 2.000 | |
| 13 | 14 | 2 | M | 1.200 | |
| 17 | 18 | 2 | M | 2.000 | |
| 19 | 20 | 2 | A | 1.333 | |
| 23 | 24 | 3 | A | 2.000 | |
| 29 | 30 | 3 | M | 2.667 | |
| 31 | 32 | 2 | A | 1.000 | |
| 37 | 38 | 2 | M | 1.059 | |
| 41 | 42 | 4 | M | 2.667 | |
| 43 | 44 | 3 | A | 1.091 | |
| 47 | 48 | 5 | O | 2.000 |
3. Elementary Structural Results
Theorem 3.1 (Mirror congruence).
If is Mirror then ; consecutive Mirror primes satisfy .
Proof.
with prime, so , giving or . If then , impossible. ◻
Corollary 3.2.
The minimum gap between consecutive Mirror primes is .
Theorem 3.3 (Anchor-3 congruence).
If is Anchor-3 then .
Proof.
If then , so , impossible for prime. ◻
Remark 3.4.
The Orphan fraction grows from at to at , consistent with conditional density-zero status of Mirror and Anchor-3 primes under the Twin Prime Conjecture.
4. The Shifted-Prime Multiplicity Conjecture
Conjecture 4.1 (Shifted-prime multiplicity).
For every prime , .
The bound is sharp: , . Three proof strategies, all out of reach:
- Path 1: for density-1 subset via Selberg sieve + circle method.
- Path 2: Asymptotic lower bound from the Hardy–Littlewood heuristic.
- Path 3: Full Goldbach-type theorem on the shifted-prime subsequence.
5. Computation
5.1. Methodology
Primes to generated by Sieve of Eratosthenes. For each : enumerate , test by lookup in the complete sieve (critical fix: a filtered array produced false violations in an earlier version). Checkpoints every primes.
5.2. Verified Range
Proposition 5.1 (Computational verification).
for every prime . Of primes, satisfy ; zero violations found. Runtime: s.
Table 2.
Global statistics of across verified ranges.
| Metric | ||||
|---|---|---|---|---|
| Primes analysed | 161 | 9 591 | 78 497 | 664 574 |
| 1 | 1 | 1 | 1 | |
| — | 2 135 | 15 594 | 100 000 | |
| 1.445 | 1.408 | 1.365 | 1.330 | |
| — | 1.742 | 1.742 | 1.742 | |
| — | — | — | 0.578 | |
| Mirror | 11.4% | 7.0% | 5.5% | 4.6% |
| Anchor-3 | 8.0% | — | 9.5% | 7.5% |
| Orphan | 81.6% | 85.1% | — | 87.5% |
| Violations | 0 | 0 | 0 | 0 |
6. The Singular Factor on the Shifted-Prime Subsequence
Hardy–Littlewood Conjecture B [2] predicts
For , i.e. , the density among primes is by Dirichlet [5], greater than the generic . The expected local factor becomes , giving
Table 3.
Divisibility density: generic integers vs. primes.
| Excess | Local factor | |||
|---|---|---|---|---|
| 3 | 0.333 | 0.500 | 1.500 | |
| 5 | 0.200 | 0.250 | 1.083 | |
| 7 | 0.143 | 0.167 | 1.033 | |
| 11 | 0.091 | 0.100 | 1.011 | |
| 13 | 0.077 | 0.083 | 1.008 |
Figure 1.
Goldbach multiplicity and Law 3 prediction (). Grey dots: observed count for a random subsample of the analysed primes, plotted against . Each dot shows how many ways can be written as a sum of two primes. The solid red curve is Law 3: with . The wide scatter is expected: the singular factor varies sharply with the prime factorisation of , producing large individual deviations from any smooth envelope. Nevertheless, the curve captures the central trend across the full range, with RMSE and of points within of the prediction.
Figure 1.
Goldbach multiplicity and Law 3 prediction (). Grey dots: observed count for a random subsample of the analysed primes, plotted against . Each dot shows how many ways can be written as a sum of two primes. The solid red curve is Law 3: with . The wide scatter is expected: the singular factor varies sharply with the prime factorisation of , producing large individual deviations from any smooth envelope. Nevertheless, the curve captures the central trend across the full range, with RMSE and of points within of the prediction.

7. Convergence of : the Main Theorem
Theorem 7.1 (Convergence and value of
).
The Euler product (4) converges absolutely, , , and as .
Proof sketch.
Table 4.
Partial product converging to .
| Primes | Tail bound | ||
| 3 | large | ||
| 24 | |||
| 168 | |||
| 1 228 | |||
| 9 591 | |||
| 78 498 |
Figure 2.
Distribution of the singular factor for primes. The histogram shows the frequency of each value of across all analysed primes. The dominant peaks occur at (when has no odd prime factors contributing to the product, rare) and especially at (when , which occurs for half of all primes by Dirichlet). The red dashed vertical line marks the empirical mean ; the orange dotted line marks the theoretical limit from Theorem 7.1. Agreement to four significant figures over cases provides strong numerical confirmation of the theorem 7.1. Note that can exceed for highly composite values of , though such events are rare.
Figure 2.
Distribution of the singular factor for primes. The histogram shows the frequency of each value of across all analysed primes. The dominant peaks occur at (when has no odd prime factors contributing to the product, rare) and especially at (when , which occurs for half of all primes by Dirichlet). The red dashed vertical line marks the empirical mean ; the orange dotted line marks the theoretical limit from Theorem 7.1. Agreement to four significant figures over cases provides strong numerical confirmation of the theorem 7.1. Note that can exceed for highly composite values of , though such events are rare.

8. Three Prediction Laws for
with .
Table 5.
Comparison of the three prediction laws (, primes).
| Law | Formula | Bias | RMSE | Cov. | Cov. |
| Law 1 | 0.3744 | 86.35% | 44.99% | ||
| Law 2 | 0.4220 | 99.76% | 0.01% | ||
| Law 3 | 0.0205 | 100.00% | 99.84% | ||
Remark 8.1 (In-sample caveat).
is fitted on the same data used for evaluation. Out-of-sample validation on is needed before treating as an asymptotic constant.
Figure 3.
Relative residuals of Law 3. Each blue dot is one prime . The solid red line at is the perfect-prediction reference; the dashed orange lines at mark the coverage band. Key statistics: and of primes lie within of Law 3, compared to RMSE of for Law 1 and for Law 2. The residuals are unbiased (centred near zero) and visibly compress as increases, consistent with the conjecture that is an exact asymptotic limit. The initial scatter at small reflects the high variability of in the low-prime regime.
Figure 3.
Relative residuals of Law 3. Each blue dot is one prime . The solid red line at is the perfect-prediction reference; the dashed orange lines at mark the coverage band. Key statistics: and of primes lie within of Law 3, compared to RMSE of for Law 1 and for Law 2. The residuals are unbiased (centred near zero) and visibly compress as increases, consistent with the conjecture that is an exact asymptotic limit. The initial scatter at small reflects the high variability of in the low-prime regime.

9. The Asymptotic Constant
Conjecture 9.1 (Closed-form normalisation).
, so the best prediction law has no fitted constants:
Table 6.
Convergence of on five disjoint ranges.
| Range | ||||
|---|---|---|---|---|
| 163 | 1.4026 | 1.7293 | 0.6143 | |
| 1 061 | 1.4451 | 1.7377 | 0.6298 | |
| 8 363 | 1.4036 | 1.7419 | 0.6103 | |
| 68 906 | 1.3591 | 1.7416 | 0.5911 | |
| 586 081 | 1.3254 | 1.7426 | 0.5761 | |
| — | — | — | 0.5738 | |
Remark 9.2.
Three regression models fitted to the cumulative all place , consistent with .
Figure 4.
Convergence of on five disjoint prime ranges. Each blue dot shows estimated independently on one of the five disjoint ranges in Table 6. The horizontal axis labels each range; the red dashed line is the conjectured limit ; the green dotted line is the alternative . The descent is monotone from the third range onward and decelerating (steps then ), which disfavours (which would require acceleration). The independent stabilisation of near across all five ranges confirms Theorem 7.1 separately from the estimation.
Figure 4.
Convergence of on five disjoint prime ranges. Each blue dot shows estimated independently on one of the five disjoint ranges in Table 6. The horizontal axis labels each range; the red dashed line is the conjectured limit ; the green dotted line is the alternative . The descent is monotone from the third range onward and decelerating (steps then ), which disfavours (which would require acceleration). The independent stabilisation of near across all five ranges confirms Theorem 7.1 separately from the estimation.

10. Spectral Analysis: FFT Residuals vs. Riemann Zeros
The residuals were interpolated onto a uniform grid of points, Hann-windowed, and FFT-transformed. Spectral peaks within of each Riemann frequency were recorded.
11. A Von Mangoldt Viewpoint
For , the heuristic bridge with leads to . This is a natural direction for future explicit-formula approaches.
12. Limitations
- Conjecture 4.1 is open beyond
- Law 3 is in-sample: is fitted on the evaluation data.
- Conjecture 9.1 rests on five data points.
Figure 5.
Cumulative convergence of (log scale in ). The blue curve traces , the value of estimated cumulatively using the first primes , plotted on a logarithmic horizontal axis. The red dashed line is (Conjecture 9.1); the orange dotted line is the extrapolated limit from regression Model 1 (); the green dotted line is . The curve begins near and descends smoothly, crossing around primes. Deceleration of the descent and proximity to support Conjecture 9.1. However, five regression data points are at the limit of reliable extrapolation; validation at would substantially reduce uncertainty.
Figure 5.
Cumulative convergence of (log scale in ). The blue curve traces , the value of estimated cumulatively using the first primes , plotted on a logarithmic horizontal axis. The red dashed line is (Conjecture 9.1); the orange dotted line is the extrapolated limit from regression Model 1 (); the green dotted line is . The curve begins near and descends smoothly, crossing around primes. Deceleration of the descent and proximity to support Conjecture 9.1. However, five regression data points are at the limit of reliable extrapolation; validation at would substantially reduce uncertainty.

- Range is exploratory by Goldbach-verification standards.
- Computation not independently reproduced; source in Appendix.
- The M/A/O taxonomy is organisational, not a structural breakthrough.
- The FFT–Riemann connection is exploratory; no statistical significance established.
13. Open Questions
- 1.
- Confirm with a sixth data point at
- 5.
- Find a closed form for in terms of
- 6.
- Prove for a density-1 subset of primes unconditionally.
- 7.
- Test analogous for subsequences ,
- 8.
- Derive analytically.
Figure 6.
FFT spectrum of Law 3 residuals vs. Riemann zeta zeros. Blue curve (log scale): as a function of frequency , computed from the Hann-windowed residuals interpolated to log-spaced points. Red vertical lines: the first 15 frequencies from the non-trivial zeros of . Across all 30 tested zeros, peaks were found within of each . Important caveat: the Riemann zeros are densely distributed on the critical line, so spectral coincidences are expected even for noise. A permutation test (randomising the prime sequence) is required to assess statistical significance. This panel is exploratory only and should not be read as evidence connecting these residuals to the Riemann Hypothesis.
Figure 6.
FFT spectrum of Law 3 residuals vs. Riemann zeta zeros. Blue curve (log scale): as a function of frequency , computed from the Hann-windowed residuals interpolated to log-spaced points. Red vertical lines: the first 15 frequencies from the non-trivial zeros of . Across all 30 tested zeros, peaks were found within of each . Important caveat: the Riemann zeros are densely distributed on the critical line, so spectral coincidences are expected even for noise. A permutation test (randomising the prime sequence) is required to assess statistical significance. This panel is exploratory only and should not be read as evidence connecting these residuals to the Riemann Hypothesis.

14. Conclusions
The strongest unconditional results: absolute convergence of as the Cesàro mean of (a consequence of Dirichlet + CRT), and two congruence theorems. The principal computation: zero violations of in primes. The principal conjecture: , which if confirmed gives the parameter-free law 8. The shifted-prime Goldbach problem has its own consistent arithmetic profile, intermediate between classical Goldbach heuristics and the analytic theory of shifted primes.
Acknowledgments of Status
This paper is experimental and structural number theory. Its central conjectures are open; strongest claims are identified as theorems, computations, or heuristics.
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