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A113542
Numbers k such that (18*k^2+1)/19 is prime.
1
18, 20, 37, 56, 58, 96, 113, 134, 151, 172, 227, 229, 246, 265, 267, 286, 305, 322, 341, 362, 398, 400, 474, 476, 493, 495, 590, 609, 626, 645, 647, 664, 683, 685, 740, 780, 799, 835, 894, 911, 932, 968, 970, 987, 1008, 1025, 1027, 1044, 1046, 1063, 1141
OFFSET
1,1
LINKS
MATHEMATICA
s={}; Do[If[PrimeQ[(18n^2+1)/19], AppendTo[s, n]], {n, 2000}]; s
PROG
(PARI) is(n)=isprime((18*n^2+1)/19) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A064271 A113541 A181453 * A075865 A250113 A182226
KEYWORD
nonn,easy
AUTHOR
Zak Seidov, Jan 13 2006
STATUS
approved