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A032486
Numbers k such that 219*2^k+1 is prime.
1
1, 2, 3, 9, 13, 14, 17, 21, 22, 25, 27, 51, 58, 99, 138, 197, 325, 386, 413, 475, 529, 771, 826, 1114, 1981, 2249, 2333, 2673, 3171, 3534, 5214, 7197, 7275, 9307, 16321, 16851, 17993, 18753, 19825, 26165, 27477, 27997, 33253, 64537, 64694, 71259, 134666
OFFSET
1,2
LINKS
MATHEMATICA
Select[Range[1000], PrimeQ[219*2^# + 1] & ] (* Robert Price, Dec 19 2018 *)
PROG
(PARI) is(n)=ispseudoprime(219*2^n+1) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A047162 A155929 A175206 * A123859 A048744 A101234
KEYWORD
nonn,hard
AUTHOR
EXTENSIONS
a(47)-a(58) from the Ray Ballinger and Wilfrid Keller link by Robert Price, Dec 19 2018
STATUS
approved