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 A009731 Expansion of tan(x)*cosh(log(1+x)). 0
 0, 1, 0, 5, -12, 96, -480, 3968, -29568, 283840, -2759040, 31139712, -369431040, 4852567552, -67622790144, 1018594276352, -16267048304640, 277008597516288, -4982377179119616, 94730142262034432, -1894021067538432000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS FORMULA a(n) ~ n! * (-1)^(n+1) * tan(1) / 2. - Vaclav Kotesovec, Jan 23 2015 MATHEMATICA CoefficientList[Series[((1 + (1 + x)^2)*Tan[x])/(2*(1 + x)), {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 23 2015 *) With[{nn=30}, CoefficientList[Series[Tan[x]*Cosh[Log[1+x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, May 05 2018 *) CROSSREFS Sequence in context: A009414 A009426 A304001 * A009427 A267271 A009754 Adjacent sequences:  A009728 A009729 A009730 * A009732 A009733 A009734 KEYWORD sign,easy AUTHOR EXTENSIONS Extended with signs by Olivier Gérard, Mar 15 1997 First previous Mathematica program replaced by Harvey P. Dale, May 05 2018 STATUS approved

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Last modified March 25 20:10 EDT 2019. Contains 321477 sequences. (Running on oeis4.)