|
|
A012839
|
|
sech(sec(x)*tanh(x))=1-1/2!*x^2+1/4!*x^4-97/6!*x^6+2945/8!*x^8...
|
|
0
|
|
|
1, -1, 1, -97, 2945, -148929, 15801729, -1624918817, 267458400513, -52723991194497, 12773658359030017, -3865567565691658721, 1370070916604727994497, -576252092267236760553793, 281775954919455982384816769, -158211465667174544221762575521
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,4
|
|
LINKS
|
|
|
MATHEMATICA
|
With[{nn=40}, Take[CoefficientList[Series[Sech[Sec[x]Tanh[x]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Jun 20 2017 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
sign
|
|
AUTHOR
|
Patrick Demichel (patrick.demichel(AT)hp.com)
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|