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A009709
E.g.f. tan(tan(x)/cosh(x)), odd powers only.
1
1, 1, 17, 593, 19425, 1598177, 158823537, 20206883505, 3739345763009, 800168319488705, 218377697922437073, 71589148444259595281, 27561852243967184213153, 12547454880768646146119585
OFFSET
1,3
LINKS
EXAMPLE
tan(tan(x)/cosh(x)) = x + 1/6*x^3 + 17/120*x^5 + 593/5040*x^7 + ...
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Tan[Tan[x]/Cosh[x]], {x, 0, nn}], x]Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, May 06 2012 *)
CROSSREFS
Sequence in context: A041547 A041544 A202407 * A162490 A296790 A330516
KEYWORD
nonn
AUTHOR
EXTENSIONS
Extended and signs tested Mar 15 1997 by Olivier Gérard.
STATUS
approved