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 A321551 a(n) = Sum_{d|n} (-1)^(d-1)*d^12. 2
 1, -4095, 531442, -16781311, 244140626, -2176254990, 13841287202, -68736258047, 282430067923, -999755863470, 3138428376722, -8918293480462, 23298085122482, -56680071092190, 129746582562692, -281543712968703, 582622237229762, -1156551128144685, 2213314919066162, -4096999772640686 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Seiichi Manyama, Table of n, a(n) for n = 1..10000 J. W. L. Glaisher, On the representations of a number as the sum of two, four, six, eight, ten, and twelve squares, Quart. J. Math. 38 (1907), 1-62 (see p. 4 and p. 8). FORMULA G.f.: Sum_{k>=1} (-1)^(k-1)*k^12*x^k/(1 - x^k). - Ilya Gutkovskiy, Dec 24 2018 PROG (PARI) apply( a(n)=sumdiv(n, d, (-1)^(d-1)*d^12), [1..30]) \\ M. F. Hasler, Nov 26 2018 CROSSREFS Cf. A321543 - A321565, A321807 - A321836 for similar sequences. Sequence in context: A024010 A123868 A321557 * A161004 A022194 A069387 Adjacent sequences:  A321548 A321549 A321550 * A321552 A321553 A321554 KEYWORD sign,mult AUTHOR N. J. A. Sloane, Nov 23 2018 STATUS approved

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Last modified December 9 09:21 EST 2019. Contains 329877 sequences. (Running on oeis4.)