login
The OEIS is supported by
the many generous donors to the OEIS Foundation
.
Hints
(Greetings from
The On-Line Encyclopedia of Integer Sequences
!)
A012670
arctan(tanh(x)*tan(x))=2/2!*x^2-128/6!*x^6+253952/10!*x^10...
1
2, -128, 253952, -2863136768, 107451055603712, -10140668012798148608, 2022780765718183801782272, -757569427466144902069404827648
(
list
;
graph
;
refs
;
listen
;
history
;
text
;
internal format
)
OFFSET
0,1
LINKS
Table of n, a(n) for n=0..7.
FORMULA
(-1)^n * 2^(6n+1) *
A090681
(n).
CROSSREFS
Sequence in context:
A086190
A024345
A012524
*
A209248
A153425
A296060
Adjacent sequences:
A012667
A012668
A012669
*
A012671
A012672
A012673
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved
Lookup
|
Welcome
|
Wiki
|
Register
|
Music
|
Plot 2
|
Demos
|
Index
|
Browse
|
More
|
WebCam
Contribute new seq. or comment
|
Format
|
Style Sheet
|
Transforms
|
Superseeker
|
Recents
The OEIS Community
| Maintained by
The OEIS Foundation Inc.
License Agreements, Terms of Use, Privacy Policy.
.
Last modified August 12 09:35 EDT 2024. Contains 375092 sequences. (Running on oeis4.)