A249383 - OEIS

A249383

Smallest odd prime number Q such that Q*2^P-1 is also prime with P Mersenne prime exponent A000043(n).

3, 3, 7, 3, 31, 7, 61, 43, 79, 19, 739, 103, 2707, 4513, 139, 13, 4027, 28027, 14029, 87151, 11257, 8677, 122449, 104161, 113287, 216211, 150097, 862009, 876721, 414949, 4590451, 1391281

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

a(32) is a 227838-digit certified prime.

Does a(n) exist for each n? - Charles R Greathouse IV, Oct 28 2014

LINKS

Table of n, a(n) for n=1..32.

PROG

(PARI) lista(nn) = {vmp = readvec("b000043.txt"); for (n=1, nn, k=2; while(!isprime(prime(k)*2^vmp[n]-1), k++); print1(prime(k), ", "); ); } \\ Michel Marcus, Oct 27 2014

CROSSREFS

Cf. A000043, A249382, A249384.

Sequence in context: A324048 A100587 A324548 * A187419 A099282 A002937

Adjacent sequences: A249380 A249381 A249382 * A249384 A249385 A249386

KEYWORD

nonn

AUTHOR

Pierre CAMI, Oct 27 2014

STATUS

approved