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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 A368142 A368145 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 September 17 14:50 EDT 2024. Contains 375987 sequences. (Running on oeis4.)