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 A031124 Expansion of (1+z)/(1-z) - 2*Sum_{m>=1} z^(m^2)/(1-z^((m+1)^2)). 1
 1, 0, 2, 2, 0, 0, 2, 2, 2, -2, 2, 2, 2, -2, 2, 2, 0, 0, 2, 2, 2, 0, 0, 2, 2, -4, 2, 2, 2, 0, 2, 0, 2, 0, 2, 2, 0, 0, 2, 2, 0, -4, 2, 2, 2, 0, 2, 2, 2, -4, 2, 2, 2, 0, 2, 2, 2, -2, 0, 2, 2, -2, 2, 2, 0, 0, 0, 0, 2, 0, 2, 2, 2, -2, 2, 2, 0, 0, 2, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Table of n, a(n) for n=0..79. N. Luzin, Function: Part II, Amer. Math. Monthly, 105 (1998), 263-270. MATHEMATICA nmax = 100; CoefficientList[Series[(1+x)/(1-x) - 2*Sum[x^(m^2)/(1 - x^((m+1)^2)), {m, 1, Floor[Sqrt[nmax]] + 1}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Oct 04 2017 *) PROG (PARI) lista(nn) = Vec((1+z)/(1-z) - 2*sum(m=1, nn, z^(m^2)/(1-z^((m+1)^2) + O(z^nn)))); \\ Michel Marcus, Oct 02 2017 CROSSREFS Cf. A031123. Sequence in context: A039972 A344834 A344837 * A063695 A081417 A133388 Adjacent sequences: A031121 A031122 A031123 * A031125 A031126 A031127 KEYWORD sign AUTHOR N. J. A. Sloane STATUS approved

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Last modified March 3 00:24 EST 2024. Contains 370499 sequences. (Running on oeis4.)