A009160 Expansion of cosh(tan(x))/cos(x).

1, 2, 20, 448, 17296, 1013600, 83547584, 9196867072, 1301697829120, 230093807905280, 49636887216382976, 12825384465418534912, 3908078275606800338944, 1386160615200497825275904

Offset

0,2

Links

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

Mathematica

Cosh[ Tan[ x ] ]/Cos[ x ] (* Even Part *)

Crossrefs

Sequence in context: A009746 A009749 A012533 * A188811 A009252 A210901

Adjacent sequences: A009157 A009158 A009159 * A009161 A009162 A009163

Keyword

nonn

Author

R. H. Hardin

Extensions

Extended and signs tested Mar 15 1997 by Olivier Gérard.

Status

approved