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A009157
Expansion of cosh(tan(sin(x))).
0
1, 1, 5, 13, -855, -38791, -747539, 59637061, 9421489105, 573991066225, -49290541346219, -20481513828195331, -2616109089676671623, 259051585957836649961, 218489079668015355338557, 45857020942077467007882293, -6052305324824723639484616287
OFFSET
0,3
MATHEMATICA
With[{nn=40}, Take[CoefficientList[Series[Cosh[Tan[Sin[x]]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Apr 22 2013 *)
CROSSREFS
Sequence in context: A007540 A290171 A157250 * A153374 A247789 A012032
KEYWORD
sign
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
More terms from Harvey P. Dale, Apr 22 2013
STATUS
approved