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A032453
Numbers k such that 153*2^k+1 is prime.
0
1, 2, 13, 16, 17, 26, 37, 62, 73, 97, 112, 286, 313, 317, 1001, 1237, 1565, 2665, 5753, 9232, 13202, 14665, 15226, 16633, 50237, 82205, 122821, 181093, 402206, 801973, 877553, 1214002, 2079401, 2697173
OFFSET
1,2
MATHEMATICA
Select[Range[1000], PrimeQ[153*2^# + 1] & ] (* Robert Price, Dec 18 2018 *)
PROG
(PARI) is(n)=ispseudoprime(153*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A042253 A041645 A318999 * A298295 A257636 A258317
KEYWORD
nonn,hard,more
AUTHOR
EXTENSIONS
a(28)-a(32) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 18 2018
a(33)-a(34) from Jeppe Stig Nielsen, Mar 12 2020
STATUS
approved