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A032390
Numbers k such that 81*2^k+1 is prime.
1
1, 4, 5, 7, 12, 15, 16, 21, 25, 27, 32, 35, 36, 39, 48, 89, 104, 121, 125, 148, 152, 267, 271, 277, 296, 324, 344, 396, 421, 436, 447, 539, 577, 592, 711, 809, 852, 1384, 1972, 2624, 2829, 3497, 3945, 3995, 4911, 5225, 5676, 5811, 7025, 7671, 8512, 10399
OFFSET
1,2
PROG
(PARI) is(n)=ispseudoprime(81*2^n+1) \\ Charles R Greathouse IV, Jun 07 2017
CROSSREFS
Sequence in context: A064401 A079337 A160934 * A372631 A112918 A138920
KEYWORD
nonn,changed
STATUS
approved