Cubic Polynomial (L = 33) – Canonical Monic Peak

Monic cubic prime-generating polynomial in canonical form

Author: Paolo Borghi · Verified run: n = 0..32 · Stop at n = 33 · Computational discovery: 3 September 2026

The Polynomial

\[P(n)=n^3+17375n^2-67426n+3247007\]
L = 33

This monic cubic polynomial generates 33 consecutive prime values in canonical form, for \(n=0,1,\ldots,32\). The run terminates at \(n=33\), where \(P(33)\) is composite.

Termination

\(P(33)=19979261=149\cdot134089\) (composite).

Genealogical peak

The value immediately preceding the canonical run is also composite:

\(P(-1)=3331807=173\cdot19259\).

Therefore the polynomial has no effective genealogical child and is a genealogical peak in the canonical monic setting.

Prime Sequence (n = 0..32)

The 33 consecutive prime values generated by P(n) are:

P(0)3247007
P(1)3196957
P(2)3181663
P(3)3201131
P(4)3255367
P(5)3344377
P(6)3468167
P(7)3626743
P(8)3820111
P(9)4048277
P(10)4311247
P(11)4609027
P(12)4941623
P(13)5309041
P(14)5711287
P(15)6148367
P(16)6620287
P(17)7127053
P(18)7668671
P(19)8245147
P(20)8856487
P(21)9502697
P(22)10183783
P(23)10899751
P(24)11650607
P(25)12436357
P(26)13257007
P(27)14112563
P(28)15003031
P(29)15928417
P(30)16888727
P(31)17883967
P(32)18914143

Compact form:

3247007, 3196957, 3181663, 3201131, 3255367, 3344377, 3468167, 3626743, 3820111, 4048277, 4311247, 4609027, 4941623, 5309041, 5711287, 6148367, 6620287, 7127053, 7668671, 8245147, 8856487, 9502697, 10183783, 10899751, 11650607, 12436357, 13257007, 14112563, 15003031, 15928417, 16888727, 17883967, 18914143.

Form Found by the Search

The computational scan first identified the translated cubic line

\[F(n)=n^3+17381n^2+2086n+3181663.\]

with a run of 33 consecutive prime values for \(n=-2,-1,\ldots,30\). The translation \(P(n)=F(n-2)\) moves the run to the canonical interval \(n=0,\ldots,32\) and yields the polynomial above.

Computational Strategy

The final search was carried out on centered representatives of monic cubic genealogical lines of the form

\[F(n)=n^3+An^2+Bn+q,\qquad q\ \text{prime}.\]

First filter: modular obstructions for p ≤ 31

For a prime p, let Np(F) denote the number of roots of F modulo p. The search imposed \(N_p(F)=0\) for every prime \(p\le31\). In the numerical domain considered, the presence of a root modulo one of these primes obstructs a block of 32 consecutive prime values, so this is a necessary condition for the target \(L\ge32\).

The 32-tuple filter

For each prime p, define

\[ \nu_{p,32}=\#\left\{k \bmod p : F(k)F(k+1)\cdots F(k+31)\equiv 0 \pmod p\right\}. \]

If \(\nu_{p,32}=p\), every possible starting residue class of a 32-value window is obstructed modulo p, and the line can be discarded without any primality test.

A cubic has at most three roots modulo p, and each root can obstruct at most 32 starting residue classes. Hence complete coverage can occur only for \(p\le96\). After the primes up to 31 have already been treated, it is sufficient to test the new complete obstructions for primes from 37 to 89.

Modular indicators

The general modular fertility indicator used in the search was

\[ S_{97}=\prod_{p\le97}\frac{1-N_p(F)/p}{1-1/p}. \]

To evaluate specifically the configuration of 32 consecutive values, the search introduced

\[ T_{32,251}=\prod_{p\le251}\frac{1-\nu_{p,32}/p}{(1-1/p)^{32}}. \]

The second indicator was not used as a hard exclusion threshold. After the necessary filters and the broad condition \(S_{97}\ge6.30\), the surviving lines were ranked by \(T_{32,251}\) and tested in descending order. Thus the predictor determined exploration priority, not final admissibility.

Predictor calibration

Before the final scan, a calibration experiment was performed on 5,503 lines already compatible with a 32-tuple. In that sample, the Pearson correlations with the maximum run length observed in the central region were approximately:

\[ \rho(\log S_{97},L)=0.259,\qquad \rho(\log T_{32,251},L)=0.309. \]

In the top 1% of the distribution, \(T_{32,251}\) concentrated 23 cases with \(L\ge10\) and 3 cases with \(L\ge15\), compared with 17 and 1 respectively for \(S_{97}\). These results were used only as statistical evidence for search prioritization, not as a deterministic criterion.

Final scan

The final search used:

\(12001\le A\le18000\), \(1800001\le q\le3400000\) with q prime, candidate starts \(-256\le k\le256\), and an initial target of \(L=32\).

QuantityValue
Combinations examined19,524,710,802,000
Survivors after the p ≤ 31 filter441,375,416
Compatible with the 32-tuple176,879,168
Lines entering the guided search165,784,253
Candidate starts after sieving106,806,941
Values submitted to Miller–Rabin126,571,360
Scan time31.52 hours

The search engine targeted a window of 32 prime values. The discovered run contains 33 values; consequently, two overlapping 32-value windows were recorded and later recognized as belonging to the same maximum run \(L=33\).

For the discovered line: \(S_{97}=7.360820004764\), \(\log T_{32,251}=65.463520889549\).

Translation Genealogy

The unique ancestor chain is obtained by repeated translations \(n\mapsto n+1\). The table below gives the complete genealogy from the root \(L=1\) to the peak \(L=33\).

LMonic cubic polynomial
1n³ + 17471n² + 1047646n + 18914143
2n³ + 17468n² + 1012707n + 17883967
3n³ + 17465n² + 977774n + 16888727
4n³ + 17462n² + 942847n + 15928417
5n³ + 17459n² + 907926n + 15003031
6n³ + 17456n² + 873011n + 14112563
7n³ + 17453n² + 838102n + 13257007
8n³ + 17450n² + 803199n + 12436357
9n³ + 17447n² + 768302n + 11650607
10n³ + 17444n² + 733411n + 10899751
11n³ + 17441n² + 698526n + 10183783
12n³ + 17438n² + 663647n + 9502697
13n³ + 17435n² + 628774n + 8856487
14n³ + 17432n² + 593907n + 8245147
15n³ + 17429n² + 559046n + 7668671
16n³ + 17426n² + 524191n + 7127053
17n³ + 17423n² + 489342n + 6620287
18n³ + 17420n² + 454499n + 6148367
19n³ + 17417n² + 419662n + 5711287
20n³ + 17414n² + 384831n + 5309041
21n³ + 17411n² + 350006n + 4941623
22n³ + 17408n² + 315187n + 4609027
23n³ + 17405n² + 280374n + 4311247
24n³ + 17402n² + 245567n + 4048277
25n³ + 17399n² + 210766n + 3820111
26n³ + 17396n² + 175971n + 3626743
27n³ + 17393n² + 141182n + 3468167
28n³ + 17390n² + 106399n + 3344377
29n³ + 17387n² + 71622n + 3255367
30n³ + 17384n² + 36851n + 3201131
31n³ + 17381n² + 2086n + 3181663
32n³ + 17378n² − 32673n + 3196957
33n³ + 17375n² − 67426n + 3247007

Reproducibility

PARI/GP

P(n)=n^3+17375*n^2-67426*n+3247007;

for(n=0,200,
  if(!isprime(P(n)),
    print("STOP n=",n," P(n)=",P(n)," fact=",factor(P(n)));
    break
  )
);

print("P(-1)=",P(-1)," fact=",factor(P(-1)));

Expected output:

STOP n=33 P(n)=19979261 fact=[149,1; 134089,1]
P(-1)=3331807 fact=[173,1; 19259,1]

Summary

Degree3 (cubic)
MonicYes
Canonical intervaln = 0..32
RunL = 33
Stopn = 33
Stop value19979261 = 149 × 134089
Peak statusGenealogical peak
P(−1)3331807 = 173 × 19259
Coefficients (a,b,c)(17375, −67426, 3247007)
Computational discovery3 September 2026

Note on Optimality

This page documents a verified canonical run of 33 consecutive prime values for a monic cubic polynomial. No claim is made here that \(L=33\) is the absolute maximum possible, nor that no other examples with equal or greater run length exist in the literature or in independent searches.

Zenodo

A Monic Cubic Polynomial Generating 33 Consecutive Prime Values

Full note, complete computational documentation, genealogy and reproducible verification.

Zenodo record 22282558

Related Work