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%I A139203 #11 Oct 08 2016 12:32:12
%S A139203 4,6,8,10,11,16,19,47,66,183,376,507,1081,1204,12111,23181
%N A139203 Numbers k such that (k!-8)/8 is prime.
%C A139203 a(17) > 25000. - _Robert Price_, Oct 08 2016
%p A139203 a:=proc(n) if isprime((1/8)*factorial(n)-1)=true then n else end if end proc: seq(a(n),n=4..550); # _Emeric Deutsch_, May 07 2008
%t A139203 a = {}; Do[If[PrimeQ[(n! - 8)/8], Print[a]; AppendTo[a, n]], {n, 1, 300}]; a
%Y A139203 Cf. A139189, A139190, A139191, A139192, A139193, A139194, A139195, A139196, A139197, A139198.
%Y A139203 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).
%K A139203 hard,more,nonn
%O A139203 1,1
%A A139203 _Artur Jasinski_, Apr 11 2008
%E A139203 2 more terms from _Emeric Deutsch_, May 07 2008
%E A139203 More terms from _Serge Batalov_, Feb 18 2015
%E A139203 a(15)-a(16) from _Robert Price_, Oct 08 2016

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