A024225 Expansion of tan(sin(x))*x/2.

0, 1, 2, -9, -428, -5475, 251382, 21193459, 276227560, -106494482439, -11901572968150, 248514536608943, 277290379883298492, 34240556133396062229, -5078626013008010061410

Offset

0,3

Links

Table of n, a(n) for n=0..14.

Formula

a(n) = A009667(n)/2. [Martin Ettl, Nov 08 2012]

Mathematica

nn = 30; t = Range[0, nn]! CoefficientList[Series[Tan[Sin[x]]*x/2, {x, 0, nn}], x]; Take[t, {1, nn, 2}] (* T. D. Noe, Nov 08 2012 *)

Crossrefs

Cf. A009667.

Sequence in context: A003818 A325619 A049299 * A266289 A000883 A086693

Adjacent sequences: A024222 A024223 A024224 * A024226 A024227 A024228

Keyword

sign

Author

R. H. Hardin

Extensions

Extended with signs Mar 1997

Status

approved