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A186687
Primes of the form k*6^m - 1, where k is a Mersenne prime (A000668) and m >= 0.
0
2, 17, 41, 107, 251, 647, 761, 1511, 23327, 27431, 139967, 3145721, 30233087, 35551871, 6530347007, 39182082047, 91424858111, 146766805631, 6847552083566591, 153558654482644991, 246511875008397311, 14215144014964850687
OFFSET
1,1
COMMENTS
Twin of A185167.
EXAMPLE
(2^1279-1)*6^1047-1 is prime.
MATHEMATICA
Union[Flatten[Table[Select[p*6^Range[0, 30] - 1, # < 10^20 && PrimeQ[#] &], {p, {3, 7, 31, 127, 8191, 131071, 524287, 2147483647, 2305843009213693951}}]]]
PROG
(Magma)
[n: n in [0..3000] | IsPrime((2^1279-1)*6^n-1)];
CROSSREFS
KEYWORD
nonn
AUTHOR
Gilbert Mozzo, Feb 25 2011
STATUS
approved