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A125907
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Numbers k such that k divides 2^4 + 3^4 + 5^4 + ... + prime(k)^4.
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4
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OFFSET
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1,2
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COMMENTS
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a(4) is less than 10^13 contradicting the previous comment. It was found using the primesieve library by Kim Walisch and gmplib. - Bruce Garner, Feb 26 2021
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LINKS
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MATHEMATICA
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a(1) = 1; s = 2^4; Do[s = s + Prime[2n]^4+Prime[2n+1]^4; If[ Mod[s, 2n+1] == 0, Print[2n+1]], {n, 1, 20000000}]
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PROG
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CROSSREFS
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Cf. A085450 = smallest m > 1 such that m divides Sum_{k=1..m} prime(k)^n.
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KEYWORD
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bref,hard,more,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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