login
A009748
Expansion of e.g.f. tan(x)*tan(sin(x)), even powers only.
2
0, 2, 12, 118, 1880, 63274, 4010212, 332200222, 32100167600, 3749943333714, 559340287979196, 106082041802123974, 24279253761809428744, 6438550081937270152314, 1958379738778789723419028
OFFSET
0,2
LINKS
MATHEMATICA
With[{nmax = 50}, CoefficientList[Series[Tan[x]*Tan[Sin[x]], {x, 0, nmax} ], x]*Range[0, nmax]!][[1 ;; ;; 2]] (* G. C. Greubel, Feb 12 2018 *)
PROG
(PARI) x='x+O('x^50); v=Vec(serlaplace(tan(x)*tan(sin(x)))); concat([0], vector(#v\2, n, v[2*n-1])) \\ G. C. Greubel, Feb 12 2018
CROSSREFS
Sequence in context: A121425 A132692 A009546 * A212414 A305051 A274305
KEYWORD
nonn
AUTHOR
EXTENSIONS
Extended and signs tested by Olivier Gérard, Mar 15 1997
STATUS
approved