A024242 Expansion of tanh(sin(x))*tan(x)/2.

0, 1, -2, 99, -2244, 182917, -13166918, 1774050663, -260505887880, 54800178181129, -13318656715497866, 4113991096987284843, -1477277623649109678924, 635278235733490892072077, -314450515401786039971942606

Offset

0,3

Links

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

Mathematica

With[{nn=30}, Take[CoefficientList[Series[Tanh[Sin[x]]*Tan[x]/2, {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Jun 04 2025 *)

Crossrefs

Cf. A009796.

Sequence in context: A212838 A024241 A278684 * A276386 A333023 A171396

Adjacent sequences: A024239 A024240 A024241 * A024243 A024244 A024245

Keyword

sign

Author

R. H. Hardin

Extensions

Extended with signs Mar 1997

Previous Mathematica program replaced by Harvey P. Dale, Jun 04 2025

Status

approved