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A009755
Expansion of e.g.f. tan(x)/cos(sin(x)), odd powers only.
1
1, 5, 41, 517, 12145, 582405, 42317081, 3759817029, 398983432289, 52888501801733, 8949712747169929, 1870731232726437509, 461089997723562652881, 130976488217164121240069, 42778996119131902973150329, 16067412656453434757397261253, 6888568425518076742074506305217
OFFSET
0,2
LINKS
MAPLE
a:= n-> (t-> t!*coeff(series(tan(x)/cos(sin(x)), x, t+1), x, t))(2*n+1):
seq(a(n), n=0..17); # Alois P. Heinz, Feb 15 2018
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Tan[x]/Cos[Sin[x]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Mar 20 2015 *)
PROG
(PARI) x='x+O('x^50); v=Vec(serlaplace(tan(x)/cos(sin(x)))); vector((#v-1)\2 , n, v[2*n-1]) \\ G. C. Greubel, Feb 12 2018
CROSSREFS
Sequence in context: A325888 A347951 A275787 * A000685 A144286 A246760
KEYWORD
nonn
AUTHOR
EXTENSIONS
Extended and signs tested by Olivier Gérard, Mar 15 1997
One additional term from and prior Mathematica program replaced by Harvey P. Dale, Mar 20 2015
STATUS
approved