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 A305320 Expansion of Product_{k>=1} (1 - x^sigma(k)). 3
 1, -1, 0, -1, 0, 1, -1, 1, -1, 2, 1, 0, -3, 0, 0, 2, 1, -2, 0, 1, 2, -1, -3, -4, 0, 3, 4, 0, -4, -1, 6, -3, 3, -9, 0, 5, 10, 0, -6, -7, 0, 6, -2, 2, -9, 6, 7, 4, -7, -7, -11, 8, 11, 3, -5, -1, -3, 9, -10, 1, -9, 0, 16, 8, 0, -4, -4, -20, 12, -8, 11, 0, -7, 14, -2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,10 LINKS Seiichi Manyama, Table of n, a(n) for n = 0..1000 MAPLE with(numtheory): seq(coeff(series(mul(1-x^sigma(k), k=1..n), x, 90), x, n), n=0..80); # Muniru A Asiru, May 31 2018 PROG (PARI) N=99; x='x+O('x^N); Vec(prod(k=1, N, 1-x^sigma(k))) CROSSREFS Cf. A000203, A111865, A305321. Sequence in context: A225203 A136255 A194812 * A159813 A157409 A245960 Adjacent sequences:  A305317 A305318 A305319 * A305321 A305322 A305323 KEYWORD sign AUTHOR Seiichi Manyama, May 30 2018 STATUS approved

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Last modified August 12 11:29 EDT 2020. Contains 336438 sequences. (Running on oeis4.)