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 A344043 a(n) = n * Sum_{d|n} sigma(d)^3 / d. 3
 1, 29, 67, 401, 221, 1943, 519, 4177, 2398, 6409, 1739, 26867, 2757, 15051, 14807, 38145, 5849, 69542, 8019, 88621, 34773, 50431, 13847, 279859, 30896, 79953, 71194, 208119, 27029, 429403, 32799, 326337, 116513, 169621, 114699, 961598, 54909, 232551, 184719, 923117, 74129, 1008417, 85227, 697339 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA G.f.: Sum_{k >= 1} sigma(k)^3 * x^k/(1 - x^k)^2. MATHEMATICA a[n_] := n * DivisorSum[n, DivisorSigma[1, #]^3/# &]; Array[a, 44] (* Amiram Eldar, May 08 2021 *) PROG (PARI) a(n) = n*sumdiv(n, d, sigma(d)^3/d); (PARI) my(N=66, x='x+O('x^N)); Vec(sum(k=1, N, sigma(k)^3*x^k/(1-x^k)^2)) CROSSREFS Cf. A060640, A226565, A226566, A344044. Sequence in context: A294615 A182332 A163426 * A165945 A226892 A183194 Adjacent sequences:  A344040 A344041 A344042 * A344044 A344045 A344046 KEYWORD nonn,mult AUTHOR Seiichi Manyama, May 08 2021 STATUS approved

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Last modified July 25 09:49 EDT 2021. Contains 346289 sequences. (Running on oeis4.)