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%I #25 Sep 08 2022 08:46:11
%S 1,4,5,6,9,10,14,21,29,30,31,39,40,44,45,46,51,56,59,60,64,65,66,70,
%T 71,75,85,96,99,100,105,109,110,111,116,124,134,136,139,144,146,159,
%U 161,170,174,175,176,179,185,190,191,195,196,204,215,216,230,234,240,251,259,265,270,274,281
%N Numbers n such that 1 + 16n^2 is prime.
%C Note the sets of 3 consecutive numbers starting with 4, 29, 44, 64, 109, 174, ..., these numbers are congruent to 4 mod 5; cf. A255635.
%p A255634:=n->`if`(isprime(1+16*n^2), n, NULL): seq(A255634(n), n=1..300); # _Wesley Ivan Hurt_, Feb 28 2015
%t Select[Range[400], PrimeQ[16 #^2 + 1] &] (* _Vincenzo Librandi_, Mar 03 2015 *)
%o (PARI) select(n->isprime(1+16*n^2), vector(300, n, n)) \\ _Colin Barker_, Mar 01 2015
%o (Magma) [n: n in [0..300] | IsPrime(16*n^2+1)]; // _Vincenzo Librandi_, Mar 03 2015
%Y Cf. A001912, A005574, A255635.
%K nonn
%O 1,2
%A _Zak Seidov_, Feb 28 2015
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