A090865 Primes p such that (p-1)/2 is prime if p == 3 (mod 4) or (p-1)/4 is prime if p == 1 (mod 4).

7, 11, 13, 23, 29, 47, 53, 59, 83, 107, 149, 167, 173, 179, 227, 263, 269, 293, 317, 347, 359, 383, 389, 467, 479, 503, 509, 557, 563, 587, 653, 719, 773, 797, 839, 863, 887, 983, 1019, 1109, 1187, 1229, 1283, 1307, 1319, 1367, 1439, 1487, 1493, 1523, 1619

Offset

1,1

Links

G. C. Greubel, Table of n, a(n) for n = 1..10000

Mathematica

Select[Prime[Range[256]], PrimeQ[(#-1)/(5-Mod[#, 4])]& ] (* Jean-François Alcover, Jul 16 2012 *)

Prog

(PARI) forprime(p=1, 1619, if (((p%4==3) && isprime((p-1)/2)==1) || ((p%4==1) && isprime((p-1)/4)), print1(p, ", "))) \\ Jinyuan Wang, Feb 09 2019

Crossrefs

Subsequence of A058500.

Union of (A005385 \ {5}) and A090866.

Sequence in context: A297176 A155760 A058500 * A296716 A191062 A106079

Adjacent sequences: A090862 A090863 A090864 * A090866 A090867 A090868

Keyword

nonn

Author

Benoit Cloitre, Feb 12 2004

Status

approved