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 A277480 E.g.f.: -tanh(x)*LambertW(-x). 4
 0, 0, 2, 6, 28, 280, 3486, 50624, 877080, 17677440, 404537050, 10360548352, 293676213876, 9126971869184, 308568877413174, 11274243944693760, 442681525701106096, 18588860836606935040, 831243363178769061426, 39436124829328468606976, 1978382154057910059275340 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Robert Israel, Table of n, a(n) for n = 0..387 FORMULA a(n) ~ tanh(exp(-1)) * n^(n-1). a(n) = Sum_{k=0..floor(n/2)-1} binomial(n,2*k+1)*(m-2*k-1)^(m-2*k-2) - Sum_{k=1..floor(n/2)} binomial(n,2*k)*a(n-2*k). - Robert Israel, Oct 26 2016 MAPLE F:= proc(m) option remember; add(binomial(m, 2*k+1)*(m-2*k-1)^(m-2*k-2), k=0..floor(m/2)-1) - add(binomial(m, 2*k)*procname(m-2*k), k=1..floor(m/2)) end proc: map(F, [\$0..30]); # Robert Israel, Oct 26 2016 MATHEMATICA CoefficientList[Series[-Tanh[x]*LambertW[-x], {x, 0, 20}], x] * Range[0, 20]! PROG (PARI) x='x+O('x^50); concat([0, 0], Vec(serlaplace(tanh(-x)*lambertw(-x))) ) \\ G. C. Greubel, Nov 05 2017 CROSSREFS Cf. A000169, A277468, A277473, A277479. Sequence in context: A256599 A002047 A126340 * A108800 A325507 A306793 Adjacent sequences:  A277477 A277478 A277479 * A277481 A277482 A277483 KEYWORD nonn AUTHOR Vaclav Kotesovec, Oct 17 2016 STATUS approved

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Last modified December 4 08:23 EST 2021. Contains 349480 sequences. (Running on oeis4.)