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A076723
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Sum_{d divides n} (-d)^d.
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2
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-1, 3, -28, 259, -3126, 46632, -823544, 16777475, -387420517, 9999996878, -285311670612, 8916100495144, -302875106592254, 11112006824734476, -437893890380862528, 18446744073726329091, -827240261886336764178, 39346408075296150201567
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OFFSET
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1,2
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LINKS
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FORMULA
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G.f.: Sum_{n>0} (-n*x)^n/(1-x^n).
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PROG
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(PARI) a(n) = sumdiv(n, d, (-d)^d); \\ Michel Marcus, Dec 22 2018
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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