A009168 Expansion of cosh(tan(x)^2).

1, 0, 12, 480, 25872, 2031360, 227781312, 34846855680, 6932161765632, 1724433365360640, 521307469175442432, 187630895361738301440, 79180079598904589094912, 38701262478049196612321280

Offset

0,3

Links

Table of n, a(n) for n=0..13.

Mathematica

Cosh[ Tan[ x ]^2 ] (* Even Part *)

Crossrefs

Sequence in context: A012467 A009083 A012681 * A012460 A012685 A012465

Adjacent sequences: A009165 A009166 A009167 * A009169 A009170 A009171

Keyword

nonn

Author

R. H. Hardin

Extensions

Extended and signs tested Mar 15 1997 by Olivier Gérard.

Status

approved