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 A009310 Expansion of log(1+log(1+tan(x))). 0
 0, 1, -2, 9, -51, 384, -3506, 38126, -479770, 6872392, -110410296, 1967181840, -38502498592, 821352161200, -18969587297792, 471608373782864, -12558441874756176, 356636706706414848, -10759204665600245888 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS FORMULA a(n) ~ (n-1)! * (-1)^(n+1) / (arctan(1-exp(-1))^n). - Vaclav Kotesovec, Jan 22 2015 MATHEMATICA Log[ 1+Log[ 1+Tan[ x ] ] ] CoefficientList[Series[Log[1 + Log[1 + Tan[x]]], {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 22 2015 *) CROSSREFS Sequence in context: A079836 A026945 A246464 * A091319 A193465 A003584 Adjacent sequences:  A009307 A009308 A009309 * A009311 A009312 A009313 KEYWORD sign,easy AUTHOR EXTENSIONS Extended with signs by Olivier Gérard, Mar 15 1997 STATUS approved

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Last modified May 12 02:06 EDT 2021. Contains 343808 sequences. (Running on oeis4.)