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 A321564 a(n) = Sum_{d divides n} (-1)^(d + n/d) * d^8. 4
 1, -257, 6562, -65281, 390626, -1686434, 5764802, -16711425, 43053283, -100390882, 214358882, -428373922, 815730722, -1481554114, 2563287812, -4278124289, 6975757442, -11064693731, 16983563042, -25500455906, 37828630724, -55090232674 (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^8*x^k/(1 + x^k). - Ilya Gutkovskiy, Dec 22 2018 PROG (PARI) apply( A321564(n)=sumdiv(n, d, (-1)^(n\d-d)*d^8), [1..30]) \\ M. F. Hasler, Nov 26 2018 CROSSREFS Column k=8 of A322083. Cf. A321543 - A321565, A321807 - A321836 for similar sequences. Sequence in context: A209533 A125648 A155468 * A034682 A017679 A013956 Adjacent sequences:  A321561 A321562 A321563 * A321565 A321566 A321567 KEYWORD sign,mult AUTHOR N. J. A. Sloane, Nov 23 2018 STATUS approved

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Last modified May 26 14:59 EDT 2020. Contains 334626 sequences. (Running on oeis4.)