A335874 Primes of the form q*2^h - 1, where q is a Mersenne prime (A000668).

2, 5, 11, 13, 23, 47, 61, 191, 223, 383, 991, 3583, 3967, 6143, 16381, 63487, 253951, 262111, 786431, 917503, 1048447, 1048573, 4194271, 14680063, 16777183, 67108351, 260046847, 3758096383, 4261412863, 51539607551, 68718952447, 266287972351, 824633720831, 1065151889407, 1099503239167

Offset: 1

Author

Antti Karttunen, Jun 28 2020

Keywords

• nonn

Comments

Primes p such that A331410(1+p) = 1. After 2, primes p for which A331410(p) = 2.

Crossrefs

Cf. A000040, A000265, A000668, A331410.

After 2, primes in A335882.

Cf. also A334092.

Programs

PARI

A000265(n) = (n>>valuation(n,2));
isA000668(n) = (isprime(n)&&!bitand(n,1+n));
isA335874(n) = (isprime(n)&&isA000668(A000265(1+n)));

Extensions

a(28)-a(35) from David A. Corneth, Jun 28 2020