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A199167
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Smallest number k such that the sum of the n-th powers of the divisors of k is divisible by n.
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2
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1, 3, 2, 15, 8, 12, 4, 105, 2, 3, 43, 60, 9, 12, 8, 945, 67, 300, 37, 240, 5, 48, 137, 420, 8, 5, 2, 60, 173, 12, 16, 10395, 86, 13, 76, 2100, 73, 147, 8, 1680, 163, 4800, 257, 240, 8, 3072, 281, 3780, 4, 3, 101, 60, 211, 14700, 8, 420, 32, 17, 353, 8400, 169
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OFFSET
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1,2
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LINKS
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EXAMPLE
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a(6) = 12 because the divisors of 12 are 1, 2, 3, 4, 6, 12 and 1^6 + 2^6 + 3^6 + 4^6 + 6^6 + 12^6 = 3037530 = 6*506255.
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MAPLE
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with(numtheory):
a:= proc(n) local k;
for k while irem (add (d &^n mod n, d=divisors(k)), n)<>0
do od; k
end:
seq (a(n), n=1..63);
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MATHEMATICA
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snk[n_]:=Module[{k=1}, While[!Divisible[DivisorSigma[n, k], n], k++]; k]; Array[ snk, 70] (* Harvey P. Dale, Jun 07 2016 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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