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 A309867 Expansion of Product_{k>0} (1+sqrt(1-4*x^k))/2. 1
 1, -1, -2, -2, -5, -9, -36, -104, -365, -1219, -4213, -14617, -51570, -183084, -656536, -2370066, -8613590, -31478538, -115632718, -426676244, -1580878746, -5878933054, -21936060630, -82100980070, -308146839623, -1159545407027, -4373730398473, -16533813947503 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS PROG (PARI) N=66; x='x+O('x^N); Vec(prod(k=1, N, (1+sqrt(1-4*x^k))/2)) (PARI) N=66; x='x+O('x^N); Vec(prod(i=1, N, 1-sum(j=1, N\i, binomial(2*j-2, j-1)*x^(i*j)/j))) CROSSREFS Convolution inverse of A322204. Cf. A115140, A327682, A327683. Sequence in context: A003228 A184713 A110182 * A304584 A193899 A208567 Adjacent sequences:  A309864 A309865 A309866 * A309868 A309869 A309870 KEYWORD sign AUTHOR Seiichi Manyama, Sep 22 2019 STATUS approved

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Last modified December 13 06:26 EST 2019. Contains 329968 sequences. (Running on oeis4.)