login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A291676 Main diagonal of A291656. 3
0, 1, 10, 3527, 123296356, 757031629267449, 1263498691933197473321646, 823340843273442113630752833831086703, 285062591046216676379736060856308430344065653125000 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
FORMULA
a(n) = ((2n-1)!!)^n * Sum_{i=1..n} 1/(2*i-1)^n.
a(n) ~ 2^(n*(2*n + 1)/2) * n^(n^2) / exp(n^2 + 1/24). - Vaclav Kotesovec, Sep 25 2020
MATHEMATICA
Table[((2*n - 1)!!)^n * Sum[1/(2*k - 1)^n, {k, 1, n}], {n, 0, 10}] (* Vaclav Kotesovec, Sep 25 2020 *)
CROSSREFS
Sequence in context: A115481 A154238 A234144 * A249851 A024139 A320983
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 29 2017
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 March 28 16:34 EDT 2024. Contains 371254 sequences. (Running on oeis4.)