Primality Certificate for (9832^2143-1)/9831

Andy Steward8,553 digits19 September 2005
Originally by A.A.D.Steward 2005

This certificate uses a theorem of Brillhart, Lehmer and Selfridge 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 39.518752% factorization of N-1:

From Factorisation
98322 · 2 · 2 · 1229
Φ29833
Φ33 · 7 · 31 · 97 · 1531
Φ613 · 37 · 103 · 1951
Φ727917 · 60423637 · 535574367833
Φ93 · 19 · 397 · 739 · 54018362934184303
Φ1471 · 12721804028870550492383
Φ1723289318029 · 10835660288549418042967319 · 30220520456299746005909030651
Φ18757 · 2467 · 483711252331637503
Φ217 · 421 · 2269 · 536844799 · 118927803153139 · 1911223542491346763
Φ34307 · p62
Φ4243 · 547 · 2089835898390619 · 16602696953436043126301999851
Φ51409 · 241639 · 83292924969408980239 · 52827126167992107015640417 · p75
Φ63c144
Φ10238047 · 2049589 · c117
Φ119239 · 1429 · 77989507 · p370
Φ126127 · 240283 · 429661 · 21728886607 · 10341480200059 · p108
Φ15347078510653 · c373
Φ238c384
Φ306928099 · 150119552856249793 · c361
Φ3572143 · 107101 · c759
Φ714248473 · c762
Φ1071p2300
Φ21422377621 · 6498829 · 14522344453 · c2277

From this partial factorization, we use sufficient of the largest prime factors of N-1 so that their product F is at least N 1/3 :

5777195309 3008526464 8602057602 7459793654 5511003533 3739432118 9938024072 6877889085 4859552515 7559034582 3976510459 3609852405 4743239111 9612691100 7204352517 1183835918 0607652025 6470775913 9919671226 2881265563 8058307630 3665692259 5014314233 9705937873 6156637246 6381180359 1423734582 4078839822 3847124377 8623159316 5043858204 1715532591 8614197473 4164380365 8865893396 7258058370 3125686368 5669254115 3590183928 2505817682 3468589777 4278018008 7468144955 1126534733 0249822262 0211989179 7862041741 5583059798 5986103337 7231375201 2689671814 0254637580 3054985336 7784760041 2891055061 6056995795 3862402549 1200923038 2052444073 9692738306 3916297216 0764120601 9859098213 3693947803 7598772655 7495191384 8496460627 5872860298 8456970012 0116662127 0904922237 9973431254 4884108275 3396901370 8010985031 7712164290 1873475661 8475649530 4394364540 3543921520 5857574211 7982176313 7741984202 6290850183 1617086025 1088853472 3709547884 0702816277 1922682495 7339608086 7881096068 6008609260 5018082661 8533978205 6579202278 1802649382 0922677078 6538618509 2878395654 7515582817 7780051307 2200551845 9419366990 4502652522 6741455352 2096953682 5288413829 4129487726 9199435091 5882364953 1653044179 2244712084 6345193097 2299111334 1514219792 2169258715 5325383492 5188225080 3575718470 1157349336 1003781638 1301376990 5158216019 8207620722 7830635908 7800096412 6392055590 7825996381 6903285140 8642683699 2210436081 7247897840 7084858469 9386515158 7113714620 6840170335 3136351463 6331341275 0272157013 0672880201 3367525924 4460779044 4246514383 2238212831 5479637103 4086227930 4668995108 3779601250 2189162010 9861675699 7174827920 0590332247 8441202541 2478613348 2951865396 9096128518 5180652492 7596871323 9129535123 8187180033 3214593472 5301414817 5119105904 1611087691 4280955655 7588297668 8830019202 1244711934 7011002451 8019963592 5877296024 3556149213 3105370298 8534965217 7773816692 1925721270 9701388742 8210731548 2896081652 6575553150 8272008405 0995632764 3920224129 3185256801 9863535518 1928578080 7916114770 6147820332 6519180048 1298632738 5747496477 1744039685 6706427859 9210697788 1234470160 5256333891 3799357744 8425108985 8586523475 7883051844 3507443262 7212933781 5707021266 9362397699 0672297303 3499521354 5206252319 6247538337 2766269061 8582223876 8530233527 1689593097 0081827229 8754033465 5454276906 3909319909 6034429127 1052494604 1934470273 8489232264 4063684724 4325230366 3358295939 6992540636 1226779806 7779959908 7185068377 8899807911 4573832826 0582156801
7380895045 2072394810 3568453355 3696657719 0903701716 0556517240 5537612042 6342074066 9687192116 2046940279 2811425648 0652619674 4568258934 3510457876 2603497575 9135399313 1589978399 6369855714 1746867951 9656233629 1131888590 3106490201 0417483632 1485529538 2099404979 3396746275 7073714018 9249523547 2219955505 4501831590 1695906979 6501447164 0352788590 5472832080 5160751681 6847580354 8603086153
18443121 8621268167 1793837870 0598404861 6100711934 4536662295 6421923806 5203396656 9312377385 7173482210 9496782573
13370 2714868753 5057165573 6228289160 3240494838 0478667875 2929421395 2649074777

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) = 33.336555%

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 = 5 suffices.

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's Theorem shows that N is prime if and only if c12-4·c2 is not a square.

Here, c12-4·c2 is ≡ 61 (mod 64) and therefore cannot be a square and N is prime.