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 A108375 Least positive k such that k * [RSA-200]^n - 1 is prime, where RSA-200 is defined in the Wikinews link. 2

%I #6 Apr 03 2023 10:36:10

%S 356,810,1364,1188,1490,4178,164,11312,26,4058,11234,3398,278,4530,

%T 2804,7248,14544,942,3504,4704,21194,2708,14636,3222,6990,948,48260,

%U 4974,6636,10646,12062,4944,28296,7302,89264,2814,35396,8688,19166,18744

%N Least positive k such that k * [RSA-200]^n - 1 is prime, where RSA-200 is defined in the Wikinews link.

%C Another term is a(51)=854. All values have been proved prime. Primality proof for a(51), which has 10175 digits: PFGW Version 1.2.0 for Windows [FFT v23.8] Primality testing 854*(279978 ... [digits deleted] ... 823983)^51-1 [N+1, Brillhart-Lehmer-Selfridge] Reading factors from helper file help.txt Running N+1 test using discriminant 5, base 4+sqrt(5) Calling Brillhart-Lehmer-Selfridge with factored part 50.07% 854*(279978 ... [digits deleted] ... 823983)^51-1 is prime! (68.4205s+0.0510s) ======== Also, the Primeform e-group found 25987968300*[RSA-200]^512-1 and 49334180280*[RSA-200]^512-1, each with 102128 digits (see link).

%H Chris Caldwell, <a href="https://t5k.org/bios/page.php?id=339">Primeform e-group bio</a>.

%H Wikinews, <a href="http://en.wikinews.org/wiki/200_digit_number_factored">200 Digit Number Factored</a>.

%K nonn

%O 1,1

%A _Jason Earls_, Jul 02 2005

%E a(12)-a(40) from _Max Alekseyev_, Feb 02 2010

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Last modified May 23 09:20 EDT 2024. Contains 372760 sequences. (Running on oeis4.)