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A193430 Primes p such that p+1 is in A055462. 1
23, 6911, 5944066965503999 (list; graph; refs; listen; history; text; internal format)
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 A090674 A013728

Adjacent sequences:  A193427 A193428 A193429 * A193431 A193432 A193433

KEYWORD

nonn,bref,hard

AUTHOR

Kausthub Gudipati, Jul 28 2011

STATUS

approved

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Last modified December 15 22:02 EST 2019. Contains 330012 sequences. (Running on oeis4.)