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A238265
Primes p such that p + 1 or p - 1 is in A055462.
1
2, 3, 23, 6911, 238878721, 5944066965503999
OFFSET
1,1
COMMENTS
Primes which are within 1 of a superduperfactorial number.
Supersequence of A193430.
FORMULA
a(n) are the prime values of 1! * (1! * 2!) * (1! * 2! * 3!) * (1! * 2! * 3! * n!) +/- 1.
EXAMPLE
A000142(2)^3*A000142(3)^2*A000142(4) - 1 = 6911, which is prime.
PROG
(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, ", ")));
CROSSREFS
Sequence in context: A225726 A076530 A360225 * A203015 A260420 A241661
KEYWORD
nonn,hard
AUTHOR
STATUS
approved