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A193430
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Primes p such that p+1 is in A055462.
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1
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OFFSET
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1,1
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COMMENTS
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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.
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LINKS
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FORMULA
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a(n) are the prime values of 1! * (1! * 2!) * (1! * 2! * 3!) * (1! * 2! * 3! * ... * n!) - 1
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EXAMPLE
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23 is a term because 23 = 1! * (1! * 2!) * (1! * 2! * 3!) - 1.
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PROG
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(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
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CROSSREFS
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KEYWORD
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nonn,bref,hard
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AUTHOR
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STATUS
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approved
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