Primality Certificate for (9592^2621-1)/9591

Andy Steward10,433 digits11 February 2010
Originally by Bernardo Boncompagni 2010

This certificate uses a theorem of Coppersmith and Howgrave-Graham to prove an integer N prime by making use of a partial prime factorization of N-1.

Factorizing N-1

As N is a Generalized Repunit, we make use of the algebraic factorization of N-1 to arrive at the following 26.569464% factorization of N-1:

From Factorisation
95922 · 2 · 2 · 11 · 109
Φ253 · 181
Φ45 · 17 · 1082429
Φ5911 · 9293163595831
Φ101381 · 6129114398101
Φ205 · 41 · 1861 · 332081 · 1200563521 · 471133461521
Φ131263 · 787 · 26987 · 102967 · 624347 · 3435869 · 7807601 · 583075499 · p475
Φ26246540134874958787437 · 33213329491779629148569 · c476
Φ52424433597 · c1028
Φ6553931 · p2067
Φ13109859061 · 121599515139111001 · 856843255826640588323330311 · c2020
Φ26202621 · c4138

We need the product F of all the prime factors from this partial factorization:

9959100 7136150031 3126307372 8748077364 2012114770 3558406948 0419794960 6340419243 4301053547 6983416018 7677232495 3937389541 8675489312 9837748457 7437348179 5692431987 8030375510 7476842632 9681648447 4588495981 3498400967 1502476448 1015361157 0775344715 2624630486 4804353190 0934104650 6985067046 7219243547 8133036140 0889482807 6679020805 5973191608 4426110203 8700343085 1946508054 5087028670 4976920376 1876129224 3313931560 3409618404 8394553708 8370113687 4867137541 5745874520 5123843791 8702660955 7699440885 5310724603 7517292514 9611235250 1039740782 8760362975 2653473511 1093704423 5602280348 4560894840 6240027942 7979817541 8787268874 8800914437 1882132789 0127800564 9490487494 1868012876 0908061400 1768787382 1656544586 0788686549 2497817317 4016402526 8320747474 1454963358 0003727431 8867850430 1939036160 6390181390 2330393213 0879768580 0359615278 4738330491 3102926264 7351556090 7542881444 3885963326 5024750996 3949762681 0177022333 5009231261 6723742621 4742818384 5016090924 8657381077 1985109746 2258867369 4769778849 1942883190 6789181698 7112897583 4491716657 6957815332 1526416128 7365281016 7210382939 7710374138 2766631471 2193500303 6657994655 0186481588 7884154289 0207862992 7664467167 8800934930 8807066087 9416048048 6897037114 6215915016 9669387810 9335046061 3212697941 3054498794 6034038910 8346407258 1909072600 7091418927 1565172555 9587155969 2977527690 3846149256 4470294355 1078010165 7505236995 2533154909 5329191157 8091231985 1607131019 7056043326 4284236629 4377789006 6677864364 9138048652 3356942066 9661247834 9178854861 0085993356 1133262228 5870734981 5372218191 1387088556 1997435265 1053076526 9064509875 4425301700 3610172326 2550948724 5648135547 0773645505 4273471047 7849293185 0612330105 1832759724 7869634628 2015562036 1715875425 5785981471 1373819679 9624984592 8476396002 8819169239 1995512753 7569246708 5456176366 1570505345 5642195634 6098842765 8260006032 0945739600 5100056684 7326147783 5379200215 8547384638 2550092900 5410376532 8301731170 6803980141 7872371458 7823336599 0142277257 1113066092 3724879029 1766962840 6052788179 6081660700 5263997521 6598246561 7033165571 5428048301 6124409818 2285790679 8473650728 7660758828 2797175822 9549394491 9063750035 8626103725 9033241503 7862668011
79204 3823335886 5886519702 3894368998 0481576280 1846685985 6830727184 2372693310 0996240439 4896481962 2012786133 7665022813 8194099672 3946045174 8740622788 7719684307 8549501361 3002243074 3251578078 2597944952 8825151925 1489155515 0362943162 7768507437 5147697074 1485458558 0492555436 1950060574 4748278807 9629913607 5817438617 0428268594 1153752724 9573974564 2873694699 4546335318 2905409960 5578233502 9990550024 9317028152 5945812063 3422321310 3413002172 7658164728 8320916140 0420156174 6469656629 8065566789
8568432 5582664058 8323330311
332 1332949177 9629148569
4654013487 4958787437
12159951 5139111001
929 3163595831
612 9114398101
47 1133461521
1200563521
583075499
24433597
9859061
7807601
3435869
1082429
624347
332081
102967
26987
3931
2621
1861
1381
911
787
263
181
109
53
41
17
11
52
23

Note that all prime factors listed above have been proven. As primes of under 250 decimal digits can be verified in a few seconds, proof of their primality is not included here, in order to save space. Larger prime factors can take from hours to months to prove; certificates for all such factors have been PKZIPped into this file.

We set R = (N-1)/F. Note that GCD(F,R)=1 and Log(F)/Log(N) = 26.569464%

Finding a Witness to Primality

Next, we find an integer witness w such that for each prime factor p of N-1, w(N-1) ≡ 1 mod N and GCD(w(N-1)/p-1,N) = 1. In this case, w = 21 suffices.

Given such a witness, Pocklington's Theorem shows that every prime factor of N ≡ 1 (mod F). As F4>N, N can have no more than three prime factors.

Express N in base F

As F2 < N < F3 and N ≡ 1 (mod F), we can let N = c2·F2 + c1·F + 1.

Brillhart, Lehmer and Selfridge

Brillhart, Lehmer and Selfridge's Theorem shows that N has exactly two prime factors if and only if c12-4·c2 is a perfect square.

Here, c12-4·c2 is ≡ 31 (mod 63) and therefore cannot be a square and this stage of the proof is passed.

Coppersmith and Howgrave-Graham

We are left with two possibilities for N: either it has exactly three prime factors or it is prime. The non-existence of exactly three factors is demonstrated by the Theorem of Coppersmith and Howgrave-Graham, here performed by a Pari/GP script written by John Renze and David Broadhurst. The input file containing N and F and the output certificate are included in this file.