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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
356, 810, 1364, 1188, 1490, 4178, 164, 11312, 26, 4058, 11234, 3398, 278, 4530, 2804, 7248, 14544, 942, 3504, 4704, 21194, 2708, 14636, 3222, 6990, 948, 48260, 4974, 6636, 10646, 12062, 4944, 28296, 7302, 89264, 2814, 35396, 8688, 19166, 18744 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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).

LINKS

Table of n, a(n) for n=1..40.

Chris Caldwell, Primeform e-group bio.

Wikinews, 200 Digit Number Factored.

CROSSREFS

Sequence in context: A241960 A221450 A232298 * A237466 A233686 A231078

Adjacent sequences:  A108372 A108373 A108374 * A108376 A108377 A108378

KEYWORD

nonn

AUTHOR

Jason Earls, Jul 02 2005

EXTENSIONS

a(12)-a(40) from Max Alekseyev, Feb 02 2010

STATUS

approved

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Last modified January 18 10:47 EST 2022. Contains 350454 sequences. (Running on oeis4.)