login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A012164 sinh(tan(arcsinh(x))) = x+2/3!*x^3+16/5!*x^5+216/7!*x^7+6400/9!*x^9... 0
1, 2, 16, 216, 6400, 125696, 18156672, -930421504, 394852151296, -97538559528960, 37824762737852416, -16526000392804139008, 8864261701679059992576, -5567468507542446595047424 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..13.

FORMULA

a(n) ~ (-1)^n * 2^(2*n+2) * n^(2*n) * cos(tanh(Pi/2)) / ((cosh(Pi)+1) * exp(2*n)). - Vaclav Kotesovec, Oct 30 2013

MATHEMATICA

Table[n!*SeriesCoefficient[Sinh[Tan[ArcSinh[x]]], {x, 0, n}], {n, 1, 40, 2}] (* Vaclav Kotesovec, Oct 30 2013 *)

CROSSREFS

Sequence in context: A012056 A062971 A267782 * A264543 A223638 A188688

Adjacent sequences:  A012161 A012162 A012163 * A012165 A012166 A012167

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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 2 19:18 EST 2021. Contains 341756 sequences. (Running on oeis4.)