A186250 2n-th derivative of sech(x)^sech(x) at x=0.

1, -1, 11, -256, 10541, -672136, 61001951, -7445096296, 1172998147241, -231333927486736, 55747918840676411, -16100914826854576456, 5485174647349481371661, -2175023364205612725532456, 992565740287786208277022391, -516241740263310751317668520736

Offset

0,3

Comments

sech(x) = 1/cosh(x).

The sequence gives only 2n-th derivatives because (2n+1)-th derivatives are 0.

Links

Table of n, a(n) for n=0..15.

Mathematica

f[x_] := Sech[x]^Sech[x]; Table[Derivative[2*n] [f][0], {n, 0, 18}]

Crossrefs

Cf. A186249.

Sequence in context: A128405 A052782 A186249 * A324327 A142208 A168466

Adjacent sequences: A186247 A186248 A186249 * A186251 A186252 A186253

Keyword

sign

Author

Michel Lagneau, Aug 18 2012

Status

approved