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A259369
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a(n) = 1 + sigma(n)^3 + sigma(n)^6.
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3
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3, 757, 4161, 117993, 46873, 2987713, 262657, 11394001, 4829007, 34018057, 2987713, 481912257, 7532281, 191116801, 191116801, 887533473, 34018057, 3518803081, 64008001, 5489105833, 1073774593, 2176828993, 191116801, 46656216001, 887533473, 5489105833
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OFFSET
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1,1
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LINKS
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FORMULA
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MAPLE
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MATHEMATICA
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Table[1 + DivisorSigma[1, n]^3 + DivisorSigma[1, n]^6, {n, 10000}]
Table[Cyclotomic[9, DivisorSigma[1, n]], {n, 10000}]
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PROG
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(PARI) a(n) = polcyclo(9, sigma(n)) \\ Michel Marcus, Jun 25 2015
(Magma) [1+SumOfDivisors(n)^3+ SumOfDivisors(n)^6: n in [1..50]]; // Vincenzo Librandi, Jun 26 2015
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CROSSREFS
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Cf. A259370 (indices of primes in this sequence), A259371 (corresponding primes).
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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