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 A139065 Numbers k for which (7+k!)/7 is prime. 25
 11, 15, 16, 25, 35, 59, 64, 68, 82, 121, 149, 238, 584, 912, 3349, 4111, 4324, 15314, 19944, 20658, 22740, 23364 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS For primes of the form (7+k!)/7, see A139064. a(23) > 25000. - Robert Price, Nov 20 2016 LINKS MATHEMATICA a = {}; Do[If[PrimeQ[(n! + 7)/7], AppendTo[a, n]], {n, 1, 500}]; a Select[Range[500], PrimeQ[(7+#!)/7]&] (* Harvey P. Dale, Sep 01 2014 *) PROG (PARI) for(k=7, 1e3, if(ispseudoprime(k!/7+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: A262721 A174952 A209898 * A186404 A111322 A069822 Adjacent sequences:  A139062 A139063 A139064 * A139066 A139067 A139068 KEYWORD nonn,hard,more AUTHOR Artur Jasinski, Apr 07 2008 EXTENSIONS More terms from Serge Batalov, Feb 18 2015 a(18)-a(22) from Robert Price, Nov 20 2016 STATUS approved

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Last modified December 13 17:37 EST 2019. Contains 329970 sequences. (Running on oeis4.)