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%I #12 Mar 02 2014 02:55:15
%S 2,3,23,6911,238878721,5944066965503999
%N Primes p such that p + 1 or p - 1 is in A055462.
%C Primes which are within 1 of a superduperfactorial number.
%C Supersequence of A193430.
%F a(n) are the prime values of 1! * (1! * 2!) * (1! * 2! * 3!) * (1! * 2! * 3! * n!) +/- 1.
%e A000142(2)^3*A000142(3)^2*A000142(4) - 1 = 6911, which is prime.
%o (PARI) t=1; p=1; for(n=1, 6, t*=n!; p*=t; if(isprime(p-1), print1(p-1, ", ")); if(isprime(p+1), print1(p+1, ", ")));
%Y Cf. A000142, A055462.
%K nonn,hard
%O 1,1
%A _Arkadiusz Wesolowski_, Feb 21 2014
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