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%I #17 Nov 27 2015 08:27:52
%S 7,239,159667199,6974263295999,2947253997913233984847871999999,
%T 98410933013201380282539536547839999999,
%U 20138421021124611879118377356171332502421503999999999
%N Primes of the form (k!-3)/3.
%C Numbers k for which (k! - 3)/3 is prime see A139056.
%C a(8) is 180 decimal digits long. See formula for more terms. - _Derek Orr_, Mar 28 2014
%F a(n) = (A139056(n)!-3)/3 for all n. - _Derek Orr_, Mar 28 2014
%t a = {}; Do[If[PrimeQ[(-3 + n!!)/3], AppendTo[a, [(-3 + n!!)/3]], {n, 1, 1000}]; a
%t Select[(Range[50]!-3)/3,PrimeQ] (* _Harvey P. Dale_, Nov 27 2015 *)
%o (PARI) for(n=1,1000,if(floor(n!/3-1)==n!/3-1,if(ispseudoprime(n!/3-1),print(n!/3-1)))) \\ _Derek Orr_, Mar 28 2014
%Y Cf. A089085, A117141, A007749, A139056.
%K nonn
%O 1,1
%A _Artur Jasinski_, Apr 07 2008
%E Definition corrected by _Derek Orr_, Mar 28 2014
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