A009675 Tan(sin(x)^2) = 2/2!*x^2 - 8/4!*x^4 + 272/6!*x^6 - 13568/8!*x^8 + ...

0, 2, -8, 272, -13568, 1048832, -128073728, 21002749952, -4567924441088, 1269483920556032, -437557299535413248, 183472013004069404672, -91918408815486181572608, 54224850406884797340188672

Offset

0,2

Links

Robert Israel, Table of n, a(n) for n = 0..226

Formula

a(n) = 2 * A024264(n).

Maple

S:= series(tan(sin(x)^2), x, 101):
seq(coeff(S, x, j)*j!, j=0..100, 2); # Robert Israel, Apr 02 2017

Mathematica

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

Crossrefs

Cf. A024264.

Sequence in context: A203317 A258161 A012296 * A012301 A296406 A215651

Adjacent sequences: A009672 A009673 A009674 * A009676 A009677 A009678

Keyword

sign

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Status

approved