A292237 Primes p such that gpf(lpf(2^p - 1) - 1) > p.

17, 19, 31, 41, 59, 61, 67, 71, 89, 101, 103, 107, 109, 127, 137, 139, 149, 157, 163, 167, 193, 199, 227, 229, 241, 257, 269, 271, 293, 311, 313, 331, 347, 349, 373, 379, 389, 401, 409, 421, 433, 449, 479, 503, 509, 521, 523, 541, 563, 599, 607, 613, 631, 647

Offset: 1

Author

Michel Marcus, Sep 12 2017

Keywords

• nonn

Comments

Complement of A291691 w.r.t. primes.

Are there infinitely many such primes? - Thomas Ordowski, Sep 12 2017

Examples

			For p=17, we have gpf(lpf(2^p - 1) - 1) = 257 which is > 17, so 17 is a term.
		

Crossrefs

Cf. A001348, A291691, A292238.

Programs

PARI

lista(nn) = forprime(p=2, nn, if (vecmax(factor(vecmin(factor(2^p-1)[, 1])-1)[, 1]) > p, print1(p, ", ")););