A139063 Numbers k for which (6+k!)/6 is prime.

3, 4, 10, 11, 13, 14, 17, 21, 82, 115, 165, 167, 173, 174, 208, 225, 380, 655, 1187, 2000, 2568, 3010, 4542, 8750, 12257, 12601, 24083

Offset

1,1

Comments

For primes of the form (6+k!)/6, see A139062.

a(28) > 25000. - Robert Price, Nov 20 2016

Links

Table of n, a(n) for n=1..27.

Mathematica

a = {}; Do[If[PrimeQ[(n! + 6)/6], AppendTo[a, n]], {n, 1, 500}]; a

Prog

(PARI) for(k=3, 1e3, if(ispseudoprime(k!/6+1), print1(k", "))) \\ Charles R Greathouse IV, Jul 15 2011

Crossrefs

Cf. A082672, A089085, A089130, A117141, A007749, A139056, A139057, A139058, A139059, A139060, A139061, A139061, A139062, A139063, A139064, A139065, A139066, A020458.

Cf. n!/m-1 is a prime: A002982, A082671, A139056, A139199-A139205; n!/m+1 is a prime: A002981, A082672, A089085, A139061, A139058, A139063, A139065, A151913, A137390, A139071 (1<=m<=10).

Sequence in context: A066861 A292564 A191192 * A224853 A225571 A191134

Adjacent sequences: A139060 A139061 A139062 * A139064 A139065 A139066

Keyword

nonn

Author

Artur Jasinski, Apr 07 2008

Extensions

a(18) and a(19) from Robert Israel, May 19 2014

More terms from Serge Batalov, Feb 18 2015

a(24)-a(27) from Robert Price, Nov 20 2016

Status

approved