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A088332
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Primes of the form n!+1.
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13
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OFFSET
| 1,1
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COMMENTS
| Of course 2 = 0!+1 = 1!+1 has two such representations.
Prime numbers that are the sum of two factorial numbers. [From Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Nov 08 2010]
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LINKS
| T. D. Noe, Table of n, a(n) for n=1..11
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FORMULA
| a(n)=A000040(q)=A000142(k)+A000142(m). [From Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Nov 08 2010]
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EXAMPLE
| 3!+1 = 7 is prime.
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MATHEMATICA
| lst={}; Do[p=n!+1; If[PrimeQ[p], AppendTo[lst, p]], {n, 0, 3*5!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Jan 27 2009]
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PROG
| (PARI) factp1prime(n)=for(x=1, n, xf=x!+1; if(isprime(xf), print1(xf", ")))
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CROSSREFS
| Cf. A002981 (values of n).
Cf. A000142. [From Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Nov 08 2010]
Sequence in context: A088252 A196303 A048979 * A131959 A202688 A021046
Adjacent sequences: A088329 A088330 A088331 * A088333 A088334 A088335
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KEYWORD
| nonn
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AUTHOR
| Cino Hilliard (hillcino368(AT)gmail.com), Nov 06 2003
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EXTENSIONS
| The next term is too large to include.
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