A024338 Expansion of log(1+x)*log(1+tan(x))/2.

0, 0, 1, -3, 15, -80, 542, -4158, 37228, -374592, 4237120, -53017712, 729890528, -10957004864, 178355968576, -3129133077376, 58889303575296, -1183497066823680, 25300855990394880, -573326855846475776

Offset

0,4

Links

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

Mathematica

With[{nn=20}, CoefficientList[Series[Log[1+x]Log[1+Tan[x]]/2, {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Oct 27 2011 *)

Crossrefs

Cf. A009422.

Sequence in context: A093889 A369085 A020044 * A253774 A003448 A229841

Adjacent sequences: A024335 A024336 A024337 * A024339 A024340 A024341

Keyword

sign

Author

R. H. Hardin

Extensions

Extended with signs, Mar 1997

Status

approved