A275770 Primes p == 5 (mod 6) that are not Sophie Germain primes.

17, 47, 59, 71, 101, 107, 137, 149, 167, 197, 227, 257, 263, 269, 311, 317, 347, 353, 383, 389, 401, 449, 461, 467, 479, 503, 521, 557, 563, 569, 587, 599, 617, 647, 677, 701, 773, 797, 821, 827, 839, 857, 863, 881, 887, 929, 941, 947, 971, 977, 983, 1061, 1091, 1097

Offset: 1

Author

Hilko Koning, Aug 08 2016

Keywords

• nonn

Crossrefs

Cf. A005384, A007528, A045979, A053176, A156543.

Programs

Mathematica

Select[Prime[Range[150]], Mod[#, 6] == 5 && \[Not] PrimeQ[2 # + 1] &]

PARI

forprime(p=1, 900, if(Mod(p, 6)==5 && !ispseudoprime(2*p+1), print1(p, ", "))) \\ Felix Fröhlich, Aug 08 2016

Formula

Subset of A156543 and subset of A045979

Intersection of A007528 and A053176. - Felix Fröhlich, Aug 08 2016