A193430 Primes p such that p+1 is in A055462.

23, 6911, 5944066965503999

Offset

1,1

Comments

Prime numbers that are one less than the product of first n superfactorials.

The next term, if it exists, has more than 75,000 digits.

Subsequence of A238265.

Links

Table of n, a(n) for n=1..3.

Formula

a(n) are the prime values of 1! * (1! * 2!) * (1! * 2! * 3!) * (1! * 2! * 3! * ... * n!) - 1

Example

23 is a term because 23 = 1! * (1! * 2!) * (1! * 2! * 3!) - 1.

Prog

(PARI) t=1; k=1; for(n=2, 100, t*=n!; k*=t; if(ispseudoprime(k-1), print1(k-1", "))) \\ Charles R Greathouse IV, Jul 28 2011

Crossrefs

Cf. A005462, A000040.

Sequence in context: A059932 A045735 A233109 * A233213 A368142 A368145

Adjacent sequences: A193427 A193428 A193429 * A193431 A193432 A193433

Keyword

nonn,bref,hard

Author

Kausthub Gudipati, Jul 28 2011

Status

approved