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 A327684 Expansion of Product_{k>0} (1 + x^k/(1 + x^k/(1 + x^k))). 2
 1, 1, 0, 4, -4, 11, -13, 39, -73, 144, -256, 559, -1116, 2188, -4317, 8804, -17591, 34992, -69815, 140097, -280416, 560077, -1119327, 2240719, -4482527, 8961129, -17920037, 35847885, -71699202, 143384383, -286760131, 573549105, -1147115913, 2294173485, -4588309651, 9176739373 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS Seiichi Manyama, Table of n, a(n) for n = 0..1000 PROG (PARI) N=66; x='x+O('x^N); Vec(prod(k=1, N, (1+3*x^k+x^(2*k))/(1+2*x^k))) CROSSREFS Cf. A000009, A268498, A327683. Sequence in context: A128499 A325859 A265206 * A231064 A302516 A254205 Adjacent sequences:  A327681 A327682 A327683 * A327685 A327686 A327687 KEYWORD sign AUTHOR Seiichi Manyama, Sep 22 2019 STATUS approved

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Last modified November 26 01:22 EST 2020. Contains 338631 sequences. (Running on oeis4.)