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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS").
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A009779 Expansion of e.g.f.: tanh(log(1+x))*log(1+x). 1
0, 0, 2, -6, 14, -20, -36, 336, 720, -38016, 524160, -5448960, 50388480, -465903360, 5010888960, -69353625600, 1155961497600, -20593469030400, 370356373094400, -6695551947571200, 124010190839808000, -2408196729028608000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..21.

FORMULA

a(n) ~ (n-1)! * (-1)^n. - Vaclav Kotesovec, Jan 24 2015

MATHEMATICA

CoefficientList[Series[(x*(2 + x)*Log[1 + x])/(2 + x*(2 + x)), {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 24 2015 *)

With[{nn=30}, CoefficientList[Series[Tanh[Log[1+x]]*Log[1+x], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Aug 26 2020 *)

CROSSREFS

Sequence in context: A067262 A107369 A151731 * A086666 A032383 A014775

Adjacent sequences:  A009776 A009777 A009778 * A009780 A009781 A009782

KEYWORD

sign,easy

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

Definition clarified and first Mathematica program replaced by Harvey P. Dale, Aug 26 2020

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 November 30 02:42 EST 2020. Contains 338781 sequences. (Running on oeis4.)