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A249383
Smallest odd prime number Q such that Q*2^P-1 is also prime with P Mersenne prime exponent A000043(n).
2
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
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
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
KEYWORD
nonn
AUTHOR
Pierre CAMI, Oct 27 2014
STATUS
approved