

A151913


Numbers n for which (8+n!)/8 is prime.


20



7, 9, 10, 12, 14, 20, 23, 24, 29, 44, 108, 2049, 3072, 4862, 8807, 15089
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OFFSET

1,1


COMMENTS

a(17) > 25000.  Robert Price, Dec 20 2016


LINKS

Table of n, a(n) for n=1..16.


MATHEMATICA

a = {}; Do[If[PrimeQ[(n! + 8)/8], AppendTo[a, n]], {n, 1, 500}]; a


PROG

(PARI) is(n)=n>6 && isprime((8+n!)/8) \\ Charles R Greathouse IV, Apr 29 2016


CROSSREFS

For primes of the form (8+k!!)/8 see A139066.
Cf. A089130, A117141, A139035, A139057, A139059, A139060, A139062, A139064, A139067.
Cf. n!/m1 is a prime: A002982, A082671, A139056, A139199A139205; n!/m+1 is a prime: A002981, A082672, A089085, A139061, A139058, A139063, A139065, A151913, A137390, A139071 (1<=m<=10).
Sequence in context: A031000 A205872 A248636 * A095034 A118621 A117933
Adjacent sequences: A151910 A151911 A151912 * A151914 A151915 A151916


KEYWORD

nonn


AUTHOR

Artur Jasinski, Apr 07 2008; definition corrected Feb 24 2010.


EXTENSIONS

More terms from Serge Batalov, Feb 18 2015
a(15)a(16) from Robert Price, Dec 20 2016


STATUS

approved



