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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
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
Sequence in context: A059932 A045735 A233109 * A233213 A368142 A368145
KEYWORD
nonn,bref,hard
AUTHOR
Kausthub Gudipati, Jul 28 2011
STATUS
approved

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Last modified March 19 03:33 EDT 2024. Contains 370952 sequences. (Running on oeis4.)