Primality Certificate for (2632^3617-1)/2631

Andy Steward12,368 digits24 February 2010
Originally by Bernardo Boncompagni & David Broadhurst 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 29.986605% factorization of N-1:

From Factorisation
26322 · 2 · 2 · 7 · 47
Φ22633
Φ45 · 5 · 277097
Φ851193 · 937417289
Φ1617 · 6257 · 21650703034189942268033
Φ32298602963041 · p44
Φ1131345153 · 58215341 · 192608036701 · 22134018786844955681 · p339
Φ226227 · 2713 · 3617 · 2286109584157667 · c359
Φ4524973 · 4192301 · 2197720277 · c747
Φ904241441073167601 · 11967840702871841 · 32139188046953100315322158769 · c1474
Φ18083203014089008278838561 · p3044
Φ36161214977 · 659853469217 · 7995732250241 · 268613447813847937 · c6081

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

1176 5057632832 4136790516 3061119920 0405639813 8134424012 1004150596 1519924667 1208388638 7059924488 1447822370 7066581342 8657788808 3723048538 2663098108 2099864589 0040423990 4842231969 1317789086 8559508093 1069052195 5172394845 2920923456 6984568590 4923988125 1117131040 6739498361 9933833945 4656997701 7786831593 2870879626 9339166093 2896903104 6406407060 9015531657 7460874406 5296727942 1747300720 5388007521 7891234115 1757185170 7613345564 1625057808 5591935224 2529969671 4276325599 9742041219 5187554337 5916040548 5521226208 3186212600 3742022082 5081540511 1779127349 3392604295 9261197655 8486935141 2246111924 3402634877 1618343882 9769565570 1818334007 2414382515 8684211624 0736480391 4542244771 0041326594 1678234425 3506983540 7653403473 0943442993 1398137364 5330103246 7210293327 5308756051 7243823568 3208629219 0521135049 2490743341 5736109552 3322575931 0245319176 8388910699 4297693347 9225414689 9760752932 4596240203 2171460175 8549945726 1331805102 1333285695 3698686618 9925251981 2265753036 1433610201 0100200562 4960904867 1718005827 7320902249 5771567158 2150064383 5511923477 1227328029 8673387114 4368165396 0968747379 1664768232 6744636289 7511314925 8197922719 1521747554 3305985060 5010701496 6058291318 1889384405 0993549864 5286379076 0864747946 5240960247 9174267615 5800208427 6797671909 3407125076 7542802158 5081980645 8574667286 5185611720 1981936702 2575437373 1179679314 2655756259 6141479909 1148169864 1038598489 9098213819 6691291337 0366448636 0816345576 5255189959 9583561208 1349898901 8742156498 4107557431 7851366554 0988033012 2585597268 3067863871 8968414489 5551529340 4762867284 0994390645 9684704329 9173879247 6545946832 0235235913 8914619764 2718787873 0318767391 0697621860 8983079743 0843620836 8416164365 5555044964 9403580969 4859845485 9359739668 1833242469 7036547553 2931060720 5040173072 2974376711 6060570213 7295689573 9745883727 3918846920 7843647231 7195029921 7351978895 3621919948 4781561523 3544655465 9888447264 8364481678 1868817753 2181738846 5373700389 8839245073 2617192080 3004429595 5450738430 6534338174 2215317628 1004204573 6271954900 1175787602 6107566771 4559509489 0631080508 1916065454 8605652880 8798124987 5625857715 1810903769 8838077205 5782515108 0904224555 4930431329 6288996938 8196942497 7410798425 8435529662 8402542722 4759417615 2015791972 8541020273 5329230559 6272298220 2649533867 1185591643 3319822363 7026084710 5426996275 6229732507 2203130057 5422687162 9675629451 6350526505 8026507009 9205964866 1856674088 1493054413 2014760479 0373084874 4503821048 0455086532 5413896387 9568112174 1279391642 0054663277 2175728189 7985891017 3020718077 9985617911 0693449656 7034997364 2659132852 5228007995 0458428187 2501594965 6504942299 6888716608 6952668089 7051669082 9883293621 2940812430 6996602982 2221467164 0285170612 3606244079 4863705564 7815805225 7951995291 8106946825 2790442021 4978926059 3781378759 9240943926 7725228728 2238250136 1141607681 4853734400 1170540917 9423676710 9104852721 1582301155 4799545485 4506970529 2118681228 6052062155 3940428553 2912386296 6334443613 8723481543 4098663904 5001367641 0692942390 8934130865 7845854864 8853573692 3860771318 4771313600 4101968101 1344023940 3799601642 6785982725 7832919921 1310020035 9397331921 8143442239 4757979403 7774165365 6161021963 5728718951 8987486005 5968687841
353704301 5334978332 1943982326 3684025125 3898647506 3500589081 7562811476 7631242696 0303533520 6919362927 1271442046 9831294043 6461359656 5771701296 5620120263 4771213682 4856531281 1451590450 3466140799 8170491131 2823350931 3811973447 5690402245 8216841190 3334420092 1911387608 7424039456 5482981044 0181711486 3212781665 3403378218 3794058359 3255364141 2907397777
1776 1516603510 6997772357 0942807035 7661320097
321391880 4695310031 5322158769
216 5070303418 9942268033
32 0301408900 8278838561
2213401878 6844955681
26861344 7813847937
1196784 0702871841
228610 9584157667
24144 1073167601
799 5732250241
65 9853469217
29 8602963041
19 2608036701
2197720277
937417289
58215341
4192301
1345153
1214977
277097
51193
6257
4973
3617
2713
2633
227
47
17
7
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) = 29.986605%

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 = 39 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 ≡ 13 (mod 64) 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. Here is the stdout:

                 GP/PARI CALCULATOR Version 2.4.2 (development)
               amd64 running linux (x86-64 kernel) 64-bit version
          compiled: Dec  9 2008, gcc-4.1.2 20071124 (Red Hat 4.1.2-42)
                 (readline v5.1 enabled, extended help enabled)

                     Copyright (C) 2000-2006 The PARI Group

PARI/GP is free software, covered by the GNU General Public License, and 
comes WITHOUT ANY WARRANTY WHATSOEVER.

Type ? for help, \q to quit.
Type ?12 for how to get moral (and possibly technical) support.

parisize = 400000000, primelimit = 20000000

Testing a PRP called "dls2632".

Pol[1, 1] with [h, u]=[4, 1] has ratio=3.715280655192518365 E-617 at X, ratio=6.787739470112804259 E-850 at Y, witness=17.
Pol[2, 1] with [h, u]=[4, 1] has ratio=6.787739470112804259 E-850 at X, ratio=5.594781745581891331 E-727 at Y, witness=17.
Pol[3, 1] with [h, u]=[4, 1] has ratio=1.7860072641053985420 E-510 at X, ratio=1.7860072641053985420 E-510 at Y, witness=11.
Pol[4, 1] with [h, u]=[4, 1] has ratio=1.7860072641053985420 E-510 at X, ratio=7.834181316568072071 E-497 at Y, witness=11.
Pol[5, 1] with [h, u]=[6, 2] has ratio=1.2462162916566370035 E-524 at X, ratio=3.121502232163474070 E-1118 at Y, witness=13.

Validated in 1 sec.

Goodbye!

The actual input file containing N and F and the output certificate are included in this file.