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A032413
Numbers k such that 127*2^k+1 is prime.
0
2, 12, 18, 24, 54, 72, 114, 180, 214, 504, 558, 964, 1098, 1420, 2764, 4322, 5582, 10538, 14634, 23970, 61054, 67318, 88958, 96744, 297350, 357840, 376162, 723530, 916980, 925012, 1472718, 1817862
OFFSET
1,1
MATHEMATICA
Select[Range[1000], PrimeQ[127*2^# + 1] & ] (* Robert Price, Dec 17 2018 *)
PROG
(PARI) is(n)=ispseudoprime(127*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Cf. A032418.
Sequence in context: A323762 A120350 A293851 * A262897 A281353 A257256
KEYWORD
nonn,more
EXTENSIONS
a(25)-a(32) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 17 2018
STATUS
approved