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A032387 Numbers k such that 75*2^k+1 is prime. 1
1, 3, 4, 6, 7, 10, 12, 34, 43, 51, 57, 60, 63, 67, 87, 102, 163, 222, 247, 312, 397, 430, 675, 831, 984, 1018, 1054, 1615, 2017, 2157, 4705, 4923, 5473, 5682, 9063, 9118, 9657, 12250, 14895, 14901, 19794, 22750, 25350, 36015, 104082, 146163, 223698, 361614 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Jeppe Stig Nielsen, Table of n, a(n) for n = 1..55

Ray Ballinger, Proth Search Page

Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300

Y. Gallot, Proth.exe: Windows Program for Finding Large Primes

Wilfrid Keller, List of primes k.2^n - 1 for k < 300

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

PROG

(PARI) is(n)=ispseudoprime(75*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A202169 A239438 A317138 * A026313 A024912 A108588

Adjacent sequences:  A032384 A032385 A032386 * A032388 A032389 A032390

KEYWORD

nonn

AUTHOR

James R. Buddenhagen

EXTENSIONS

More terms (from http://web.archive.org/web/20161028080239/http://www.prothsearch.net/riesel.html), Joerg Arndt, Apr 07 2013

Terms moved from Data section to b-file, and more terms appended to b-file, by Jeppe Stig Nielsen, Jan 18 2020

STATUS

approved

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Last modified May 8 17:26 EDT 2021. Contains 343666 sequences. (Running on oeis4.)