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 A113706 Expansion of Product_{k>0} (1-x^(3k))/(1-x^(3k-2)). 2
 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, -1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, -1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, -1, 1, 1, -1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, -1, 0, 0, 0, 1, 1, 0, 1, 0, -1, 1, 1, -1, 0, 1, -1, 0, 2, 0, -1, 1, 0, -1, 1, 1, 0, 1, 0, -1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,93 COMMENTS |a(n)|<2 if n<92, |a(n)|<3 if n<204. LINKS Seiichi Manyama, Table of n, a(n) for n = 0..10000 FORMULA Euler transform of period 3 sequence [1, 0, -1, ...]. G.f.: Product_{k>0} (1-x^(3k))/(1-x^(3k-2)). PROG (PARI) {a(n)=if(n<0, 0, polcoeff( prod(k=1, n, (1-x^k)^([1, -1, 0][k%3+1]), 1+x*O(x^n)), n))} CROSSREFS Cf. A143240. Sequence in context: A141571 A164067 A305490 * A279952 A054845 A317991 Adjacent sequences:  A113703 A113704 A113705 * A113707 A113708 A113709 KEYWORD sign AUTHOR Michael Somos, Nov 06 2005 STATUS approved

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Last modified July 17 16:38 EDT 2019. Contains 325107 sequences. (Running on oeis4.)