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A036780
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Primes of the form n + Sum_{i=1..n} i!.
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0
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OFFSET
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1,1
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COMMENTS
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Indices that give primes: 1, 2, 4, 10. - Michel Marcus, Jan 06 2014
a(5) corresponds to index 1006 and has 2586 decimal digits. - Giovanni Resta, Jan 06 2014
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LINKS
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MATHEMATICA
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With[{nn=40}, Select[Total/@Thread[{Range[nn], Accumulate[Range[ nn]!]}], PrimeQ]] (* Harvey P. Dale, Feb 18 2018 *)
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PROG
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(PARI) lista(nn) = { for (n=1, nn, if (isprime(p = sum(i=1, n, i!) + n), print1(p, ", ")); ); } \\ Michel Marcus, Jan 06 2014
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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