A205172 Primes p == 5 (mod 8) such that p + 2 is also prime.

5, 29, 101, 149, 197, 269, 461, 821, 1061, 1229, 1277, 1301, 1877, 1949, 1997, 2141, 2237, 2309, 2381, 2549, 2789, 3389, 3461, 3557, 3581, 3821, 3917, 4157, 4229, 4421, 4517, 4637, 5021, 5477, 5501, 5741, 6197, 6269, 6701, 6869, 7349, 7589, 7757, 7877

Offset: 1

Author

Robert G. Wilson v, Jan 22 2012

Keywords

• easy
• nonn

Comments

The lesser of twin primes == 5 (mod 8).

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A071695, A205171.

Programs

Maple

select(t -> isprime(t) and isprime(t+2), [seq(i,i=5..10000,8)]);# Robert Israel, Nov 25 2019

Mathematica

Select[ Prime@ Range@ 1000, Mod[#, 8] == 5 && PrimeQ[# + 2] &]

PARI

forprime(p=1, 7900, if(Mod(p, 8)==5 && ispseudoprime(p+2), print1(p, ", "))) \\ Felix Fröhlich, Nov 25 2019