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 A321563 a(n) = Sum_{d divides n} (-1)^(d + n/d) * d^7. 3
 1, -129, 2188, -16257, 78126, -282252, 823544, -2080641, 4785157, -10078254, 19487172, -35570316, 62748518, -106237176, 170939688, -266321793, 410338674, -617285253, 893871740, -1270094382, 1801914272, -2513845188, 3404825448, -4552442508 (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^7*x^k/(1 + x^k). - Ilya Gutkovskiy, Dec 22 2018 PROG (PARI) apply( A321563(n)=sumdiv(n, d, (-1)^(n\d-d)*d^7), [1..30]) \\ M. F. Hasler, Nov 26 2018 CROSSREFS Column k=7 of A322083. Cf. A321543 - A321565, A321807 - A321836 for similar sequences. Sequence in context: A230187 A240417 A088719 * A034681 A017677 A013955 Adjacent sequences:  A321560 A321561 A321562 * A321564 A321565 A321566 KEYWORD sign,mult AUTHOR N. J. A. Sloane, Nov 23 2018 STATUS approved

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Last modified January 25 16:42 EST 2020. Contains 331245 sequences. (Running on oeis4.)