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A139063 Numbers k for which (6+k!)/6 is prime. 25
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified May 30 23:25 EDT 2020. Contains 334747 sequences. (Running on oeis4.)