A024336 Expansion of e.g.f.: tan(log(1+x)^2)/2.

0, 0, 1, -3, 11, -50, 394, -4284, 51708, -653904, 8861256, -132180840, 2186984040, -39706739280, 779193951600, -16356660384960, 365503727198400, -8673545006246400, 218077259881872000, -5792698031011056000

Offset

0,4

Links

Table of n, a(n) for n=0..19.

Mathematica

With[{nn=20}, CoefficientList[Series[Tan[Log[1+x]^2]/2, {x, 0, nn}], x]Range[0, nn]!] (* Harvey P. Dale, Sep 19 2012 *)

Crossrefs

Cf. A009655.

Sequence in context: A321607 A024335 A203009 * A145144 A367560 A284702

Adjacent sequences: A024333 A024334 A024335 * A024337 A024338 A024339

Keyword

sign

Author

R. H. Hardin

Extensions

Extended with signs Mar 1997

Definition clarified by Harvey P. Dale, Sep 19 2012

Status

approved