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A186250 2n-th derivative of sech(x)^sech(x) at x=0. 1
1, -1, 11, -256, 10541, -672136, 61001951, -7445096296, 1172998147241, -231333927486736, 55747918840676411, -16100914826854576456, 5485174647349481371661, -2175023364205612725532456, 992565740287786208277022391, -516241740263310751317668520736 (list; graph; refs; listen; history; text; internal format)
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

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Last modified August 7 04:39 EDT 2020. Contains 336274 sequences. (Running on oeis4.)