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A185167 Primes of the form k*6^m +1 where k is a Mersenne prime (A000668) and m is an integer. 3
19, 43, 109, 1117, 3889, 40177, 139969, 326593, 839809, 4718557, 5038849, 5925313, 18874333, 52068097, 1088391169, 1874451457, 6115248577, 24461134273, 1410554953729, 2429289086977, 31701630016513, 118486616113153 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..22.

EXAMPLE

(2^521-1)*6^959+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) (For the Mersenne prime 2^521-1, for example): [n: n in [0..1000] | IsPrime((2^521-1)*6^n+1)];

CROSSREFS

Cf. A000668, A185069.

Sequence in context: A054820 A165567 A205533 * A140619 A229765 A058829

Adjacent sequences:  A185164 A185165 A185166 * A185168 A185169 A185170

KEYWORD

nonn

AUTHOR

Gilbert Mozzo, Feb 18 2011

EXTENSIONS

Partially edited by N. J. A. Sloane, Feb 19 2011

STATUS

approved

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Last modified July 5 20:21 EDT 2020. Contains 335473 sequences. (Running on oeis4.)