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A032461
Numbers k such that 169*2^k+1 is prime.
0
2, 14, 26, 158, 282, 298, 406, 522, 534, 1050, 1470, 1478, 1614, 1970, 2570, 5054, 5166, 6238, 9614, 14026, 49602, 63686, 70110, 76934, 109666, 167734, 223590, 602070, 801578, 1327114, 1635086, 2545526
OFFSET
1,1
MATHEMATICA
Select[Range[1000], PrimeQ[169*2^# + 1] & ] (* Robert Price, Dec 18 2018 *)
PROG
(PARI) is(n)=ispseudoprime(169*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A109080 A295083 A180877 * A072390 A213136 A117705
KEYWORD
nonn,hard,more
AUTHOR
EXTENSIONS
a(23)-a(31) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 18 2018
a(32) from Jeppe Stig Nielsen, Apr 04 2020
STATUS
approved