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 A009611 Expansion of sinh(tan(x)*x). 3
 0, 2, 8, 216, 8896, 553120, 48069504, 5564225408, 827281160192, 153537251480064, 34761966006691840, 9422306473314752512, 3010196845995598430208, 1118714469509146379657216, 478278367951534466053799936, 232972682112352062801913282560 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Vaclav Kotesovec, Table of n, a(n) for n = 0..238 Vaclav Kotesovec, Graph - asymptotic ratio FORMULA a(n) ~ n^(2*n-1/4) * 2^(4*n-3/4) * exp(2*sqrt(2*n)-2*n-1/2) / Pi^(2*n) * (1 - (Pi^2-1)/(12*sqrt(2*n))). - Vaclav Kotesovec, Jan 24 2015 MATHEMATICA With[{nn=40}, Take[CoefficientList[Series[Sinh[Tan[x]*x], {x, 0, nn}], x] Range[ 0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Jun 23 2014 *) CROSSREFS Sequence in context: A012297 A000893 A030177 * A015176 A013345 A013343 Adjacent sequences:  A009608 A009609 A009610 * A009612 A009613 A009614 KEYWORD nonn AUTHOR EXTENSIONS Extended and signs tested Mar 15 1997 by Olivier Gérard. Prior Mathematica program replaced by and more terms from Harvey P. Dale, Jun 23 2014 STATUS approved

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Last modified February 24 19:27 EST 2020. Contains 332209 sequences. (Running on oeis4.)