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A055715
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Numbers k such that k | sigma_11(k).
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2
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1, 6, 28, 120, 402, 496, 644, 672, 920, 1366, 1608, 1932, 2680, 2760, 3417, 3966, 4098, 4623, 4975, 5152, 6210, 6834, 8040, 8128, 8280, 9246, 9528, 9950, 12294, 13668, 15008, 15456, 15864, 16392, 18492, 19900, 24120, 24840, 25954, 27320, 27336, 29850, 30240, 32760
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OFFSET
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1,2
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COMMENTS
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sigma_11(k) is the sum of the 11th powers of the divisors of k (A013959).
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LINKS
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MATHEMATICA
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Do[If[Mod[DivisorSigma[11, n], n]==0, Print[n]], {n, 1, 40000}]
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PROG
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(PARI) isok(k) = (sigma(k, 11) % k) == 0; \\ Michel Marcus, Nov 09 2019
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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a(37)-a(40) corrected and more terms added by Amiram Eldar, Nov 09 2019
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STATUS
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approved
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