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A335874
Primes of the form q*2^h - 1, where q is a Mersenne prime (A000668).
5
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.
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
After 2, primes in A335882.
Cf. also A334092.
Sequence in context: A345707 A113305 A095078 * A062572 A215214 A221868
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 28 2020
EXTENSIONS
a(28)-a(35) from David A. Corneth, Jun 28 2020
STATUS
approved