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A009069 Expansion of e.g.f. cos(tan(tanh(x))), even terms only. 1
1, -1, 1, 47, -1343, 8671, 2436545, -249528945, 10176663169, 1606374108095, -482969577637247, 59264468409177327, 4209524591120115521, -4541227341778149686881, 1235175100383899185304129 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,4
LINKS
MATHEMATICA
With[{nmax = 60}, CoefficientList[Series[Cos[Tan[Tanh[x]]], {x, 0, nmax}], x]*Range[0, nmax]!][[1 ;; -1 ;; 2]] (* G. C. Greubel, Jul 24 2018 *)
PROG
(PARI) x='x+O('x^50); v=Vec(serlaplace(cos(tan(tanh(x))))); vector(#v\2, n, v[2*n-1]) \\ G. C. Greubel, Jul 24 2018
CROSSREFS
Sequence in context: A182019 A270501 A047911 * A348805 A285237 A157359
KEYWORD
sign
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
STATUS
approved

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Last modified March 28 22:04 EDT 2024. Contains 371254 sequences. (Running on oeis4.)