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%I #10 Jan 13 2015 01:43:39
%S 2,3,5,29,727,3628811,
%T 80658175170943878571660636856403766975289505440883277824000000000053
%N Primes of the form n! + n + 1.
%C a(5) = 3628811 and a(6), a 68-digit number, have been certified prime with Primo.
%F a(k) = A073308(k)! + A073308(k) + 1.
%e a(4) = 6! + 6 + 1 = 727, a prime, so 727 is in this sequence (6 = A073308(4)).
%t f[n_]:=n!+n+1; lst={};Do[p=f[n];If[PrimeQ[p],AppendTo[lst,p]],{n,0,2*5!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jul 02 2009 *)
%o (PARI) for(n=0,1960,p=n!+n+1; if(isprime(p),print1(p,",")))
%Y Cf. A073308 (corresponding n).
%K nonn
%O 1,1
%A _Rick L. Shepherd_, Jul 24 2002
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