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 A238265 Primes p such that p + 1 or p - 1 is in A055462. 1

%I

%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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Last modified December 1 22:12 EST 2021. Contains 349435 sequences. (Running on oeis4.)