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A079649
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Numbers n such that n! + n^2 + n + 1 is prime.
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1
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OFFSET
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1,2
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LINKS
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Table of n, a(n) for n=1..6.
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EXAMPLE
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1!+1^2+1+1 = 1+1+1+1 = 4, which is not prime. 2!+2^2+2+1 = 2+4+2+1 = 8, which is not prime. 3!+3^2+3+1 = 6+9+3+1 = 19, which is prime, so a(1)=3.
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MATHEMATICA
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For[i = 1, i < 1000, If[PrimeQ[Factorial[i] + i^2 + i + 1] == True, Print[i]]; i++ ]
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CROSSREFS
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Sequence in context: A024862 A025106 A203193 * A024867 A025111 A032619
Adjacent sequences: A079646 A079647 A079648 * A079650 A079651 A079652
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KEYWORD
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nonn
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AUTHOR
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Neil Fernandez, Jan 22 2003
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STATUS
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approved
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