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 A009424 Expansion of log(1+x)/cos(log(1+x)). 1
 0, 1, -1, 5, -24, 154, -1170, 10394, -105392, 1201524, -15210180, 211691380, -3212711040, 52801793160, -934299180360, 17708685967400, -357960437635200, 7686847410694800, -174756587308650000, 4193327411934706000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS FORMULA a(n) ~ n! * (-1)^(n+1) * Pi / (2 * (exp(Pi/2)-1) * (1-exp(-Pi/2))^n). - Vaclav Kotesovec, Jan 23 2015 MATHEMATICA Log[ 1+x ]/Cos[ Log[ 1+x ] ] CoefficientList[Series[Log[1 + x]*Sec[Log[1 + x]], {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 23 2015 *) CROSSREFS Sequence in context: A322208 A241134 A340358 * A184597 A009601 A009676 Adjacent sequences: A009421 A009422 A009423 * A009425 A009426 A009427 KEYWORD sign,easy AUTHOR EXTENSIONS Extended with signs by Olivier Gérard, Mar 15 1997 STATUS approved

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Last modified February 2 19:34 EST 2023. Contains 360024 sequences. (Running on oeis4.)