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

1,1

Comments

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

Links

Table of n, a(n) for n=1..35.

Prog

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

Crossrefs

Cf. A000040, A000265, A000668, A331410.

After 2, primes in A335882.

Cf. also A334092.

Sequence in context: A345707 A113305 A095078 * A062572 A215214 A221868

Adjacent sequences: A335871 A335872 A335873 * A335875 A335876 A335877

Keyword

nonn

Author

Antti Karttunen, Jun 28 2020

Extensions

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

Status

approved