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A347894
E.g.f.: Product_{k>=1} (1 + x^k)^tan(x).
2
1, 0, 2, 3, 52, 110, 2690, 11676, 247952, 1434600, 37576168, 296088760, 7698854216, 78083294640, 2187100997328, 27174552638520, 806871808214016, 11698163585372736, 370098862531800000, 6300404006917434624, 208037772410558058624, 4032385785901175122560, 141272996628892396692096
OFFSET
0,3
FORMULA
E.g.f.: exp( tan(x) * Sum_{k>=1} x^k / (k*(1 - x^(2*k))) ). - Ilya Gutkovskiy, Sep 18 2021
E.g.f.: exp( tan(x) * Sum_{k>=1} A000593(k)*x^k/k ). - Seiichi Manyama, Sep 18 2021
PROG
(PARI) N=40; x='x+O('x^N); Vec(serlaplace(prod(k=1, N, (1+x^k)^tan(x))))
(PARI) N=40; x='x+O('x^N); Vec(serlaplace(exp(tan(x)*sum(k=1, N, sigma(k>>valuation(k, 2))*x^k/k))))
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 18 2021
STATUS
approved