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

2

`%I #12 Oct 28 2014 01:35:03
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`%S 3,3,7,3,31,7,61,43,79,19,739,103,2707,4513,139,13,4027,28027,14029,
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`%T 87151,11257,8677,122449,104161,113287,216211,150097,862009,876721,
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`%U 414949,4590451,1391281
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`%N Smallest odd prime number Q such that Q*2^P-1 is also prime with P Mersenne prime exponent A000043(n).
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`%C a(32) is a 227838-digit certified prime.
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`%C Does a(n) exist for each n? - _Charles R Greathouse IV_, Oct 28 2014
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`%o (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
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`%Y Cf. A000043, A249382, A249384.
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`%K nonn
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`%O 1,1
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`%A _Pierre CAMI_, Oct 27 2014
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