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 A012536 tan(sinh(x)*arcsin(x))=2/2!*x^2+8/4!*x^4+320/6!*x^6+15808/8!*x^8... 0
 0, 2, 8, 320, 15808, 1429888, 189299200, 34859305728, 8524943044608, 2667935751684096, 1040196824976736256, 494214397360327786496, 281064144909266002903040, 188495115535527543004266496 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Table of n, a(n) for n=0..13. FORMULA a(n) ~ 4 * (2*n)! / ((Pi/tanh(r) + 2*sinh(r)/sqrt(1-r^2)) * r^(2*n+1)), where r = 0.980280472307130556844984772871395757744942110943939753792691... is the root of the equation sinh(r)*arcsin(r) = Pi/2. - Vaclav Kotesovec, Feb 06 2015 MATHEMATICA nn = 20; Table[(CoefficientList[Series[Tan[ArcSin[x]*Sinh[x]], {x, 0, 2*nn}], x] * Range[0, 2*nn]!)[[n]], {n, 1, 2*nn+1, 2}] (* Vaclav Kotesovec, Feb 06 2015 *) CROSSREFS Sequence in context: A012913 A217728 A013086 * A012541 A054943 A013135 Adjacent sequences: A012533 A012534 A012535 * A012537 A012538 A012539 KEYWORD nonn AUTHOR Patrick Demichel (patrick.demichel(AT)hp.com) EXTENSIONS a(0)=0 prepended by Vaclav Kotesovec, Feb 06 2015 STATUS approved

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Last modified December 5 10:56 EST 2023. Contains 367589 sequences. (Running on oeis4.)