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A055707
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Numbers k such that k | sigma_13(k) - phi(k)^13.
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1
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1, 2, 12, 34, 42, 90, 170, 198, 402, 434, 456, 482, 494, 2046, 4086, 4518, 7520, 7605, 8622, 9632, 10924, 28280, 51570, 51714, 74124, 77724, 100172, 139653, 143136, 176760, 294588, 399980, 471826, 675356, 690534, 1358360, 1577696, 2089074, 2121940, 2136256
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OFFSET
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1,2
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COMMENTS
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sigma_13(k) is the sum of the 13th powers of the divisors of k (A013961).
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LINKS
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Amiram Eldar, Table of n, a(n) for n = 1..100
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MATHEMATICA
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Do[If[Mod[DivisorSigma[13, n]-EulerPhi[n]^13, n]==0, Print[n]], {n, 1, 10^5}]
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PROG
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(PARI) isok(n) = !((sigma(n, 13) - eulerphi(n)^13) % n); \\ Michel Marcus, Mar 02 2014
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CROSSREFS
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Cf. A000010, A013961.
Sequence in context: A305330 A320542 A242709 * A055699 A244378 A062094
Adjacent sequences: A055704 A055705 A055706 * A055708 A055709 A055710
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KEYWORD
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nonn
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AUTHOR
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Robert G. Wilson v, Jun 09 2000
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EXTENSIONS
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Definition corrected and more terms from Michel Marcus, Mar 02 2014
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STATUS
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approved
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