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A357056
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Integers k such that k^k + k^2 + 2*k + 1 is prime.
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0
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OFFSET
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1,3
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COMMENTS
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The next prime (if any) is unknown, but it must exceed 2000^2000 + 2000^2 + 2*2000 + 1 (a 6603-digit number).
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LINKS
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EXAMPLE
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If k = 2, then k^k + k^2 + k*2 + 1 = 2^2 + 2^2 + 2*2 + 1 = 13, which is prime.
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CROSSREFS
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KEYWORD
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nonn,more,hard
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AUTHOR
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STATUS
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approved
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