OFFSET
0,1
FORMULA
G.f.: sin(tanh(x)*tan(x)).
(* [ x^(4n+2) ] *)
EXAMPLE
sin(tanh(x)*tan(x)) = 2/2!*x^2-8/6!*x^6-159328/10!*x^10...
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Sin[Tanh[x]Tan[x]], {x, 0, nn}], x] Range[0, nn]!, {3, -1, 4}]] (* Harvey P. Dale, Sep 16 2023 *)
CROSSREFS
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
Corrected by and prior Mathematica program replaced by Harvey P. Dale, Sep 16 2023
STATUS
approved