|
|
A012395
|
|
sech(tan(x)*tan(x))=1-12/4!*x^4-480/6!*x^6-15792/8!*x^8...
|
|
1
|
|
|
1, 0, -12, -480, -15792, 387840, 232592448, 44951262720, 4538494871808, -1173690989322240, -1020600368000166912, -406075179314308669440, -50036577406600515366912, 87776293107173235762462720
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
LINKS
|
|
|
MATHEMATICA
|
With[{nn=30}, Take[CoefficientList[Series[Sech[Tan[x]^2], {x, 0, nn}], x] Range[ 0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Feb 27 2013 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
sign
|
|
AUTHOR
|
Patrick Demichel (patrick.demichel(AT)hp.com)
|
|
STATUS
|
approved
|
|
|
|