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A009085
Expansion of e.g.f. cos(tanh(sin(x))), even powers only.
1
1, -1, 13, -373, 19097, -1522409, 174263717, -27072485469, 5477315064625, -1398343023229393, 439386703590146365, -166541598232670049093, 74891796652158938855881, -39404384075265527597485241
OFFSET
0,3
LINKS
MAPLE
seq(coeff(series(factorial(n)*cos(tanh(sin(x))), x, n+1), x, n), n=0..30, 2); # Muniru A Asiru, Jul 25 2018
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Cos[Tanh[Sin[x]]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Nov 20 2015 *)
PROG
(PARI) x='x+O('x^50); v=Vec(serlaplace(cos(tanh(sin(x))))); vector(#v\2, n, v[2*n-1]) \\ G. C. Greubel, Jul 25 2018
CROSSREFS
Sequence in context: A280796 A183472 A009040 * A012013 A082403 A171656
KEYWORD
sign
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
Prior Mathematica program replaced by Harvey P. Dale, Nov 20 2015
STATUS
approved