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A015768
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Numbers k such that phi(k) | sigma_10(k).
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10
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1, 2, 3, 6, 22, 33, 66, 166, 250, 375, 498, 750, 1506, 1826, 5478, 8250, 10375, 10873, 16566, 17762, 20750, 21746, 31125, 32619, 41666, 53286, 62250, 62499, 65238, 98250, 110066, 119603, 124998, 177153, 195382, 228250, 239206
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OFFSET
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1,2
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COMMENTS
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sigma_10(k) = A013958(k) is the sum of the 10th powers of the divisors of k.
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LINKS
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MATHEMATICA
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Select[Range[240000], Divisible[DivisorSigma[10, #], EulerPhi[#]] &] (* Amiram Eldar, Nov 06 2019 *)
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PROG
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(Magma) [k:k in [1..240000]| IsIntegral(DivisorSigma(10, k)/EulerPhi(k))]; // Marius A. Burtea, Nov 06 2019
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CROSSREFS
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Cf. A020492, A015759, A015761, A015762, A015763, A015764, A015765, A015766, A015767, A015769, A015770, A015771, A015773, A015774, A094470.
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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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