A024333 Expansion of e.g.f: tanh(log(1+x)^2)/2.

0, 0, 1, -3, 11, -50, 154, 756, -25572, 434736, -6324264, 84312360, -1014504360, 9750096720, -26179417200, -2263442045760, 92224441646400, -2623899775526400, 64132749053646720, -1393649719639125120, 25953090802663939200, -339671851067737440000

Offset

0,4

Links

Table of n, a(n) for n=0..21.

Mathematica

With[{nn=30}, CoefficientList[Series[Tanh[Log[1+x]^2]/2, {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Jun 22 2019 *)

Crossrefs

Cf. A009789.

Sequence in context: A265905 A058733 A203163 * A024334 A162477 A115081

Adjacent sequences: A024330 A024331 A024332 * A024334 A024335 A024336

Keyword

sign

Author

R. H. Hardin

Extensions

Extended with signs, Mar 1997

Definition clarified and prior Mathematica program replaced by ~~~

Status

approved