

A271392


Integers n such that 3*n!!! + 1 is prime where n!!! is A007661(n).


1



2, 4, 5, 8, 9, 15, 16, 23, 27, 32, 34, 35, 38, 40, 46, 54, 57, 83, 87, 97, 162, 165, 223, 235, 282, 488, 503, 575, 673, 823, 857, 885, 965, 1112, 1401, 2288, 2569, 2788, 3133, 3539, 4070, 4654, 5020, 5613, 6720, 7773
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OFFSET

1,1


COMMENTS

Corresponding primes are 7, 13, 31, 241, 487, 87481, 174721, 289027201, 21427701121, ...


LINKS

Table of n, a(n) for n=1..46.


EXAMPLE

4 is a term because 3*4!!! + 1 = 13 is prime.


CROSSREFS

Cf. A007661, A037083, A084438, A217647, A215779, A271396.
Sequence in context: A065300 A080403 A280050 * A195364 A279793 A305076
Adjacent sequences: A271389 A271390 A271391 * A271393 A271394 A271395


KEYWORD

nonn,more


AUTHOR

Altug Alkan, Apr 06 2016


STATUS

approved



