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!)
A345646 a(n) = Sum_{k=0..n} (4*n)! / (k! * (n-k)!)^4. 2

%I #10 Jun 21 2021 10:02:03

%S 1,48,45360,60614400,114144030000,249344297250048,609148118181867264,

%T 1604207350254328934400,4471935609925802450718000,

%U 13022708340511827298941600000,39267738740263529465273799855360,121811974529188978353365962361671680,386880842128109815466159332537704902400

%N a(n) = Sum_{k=0..n} (4*n)! / (k! * (n-k)!)^4.

%C In general, for fixed m >= 1, Sum_{k=0..n} (m*n)! / (k!*(n-k)!)^m ~ (2*m)^(m*n) / (Pi*n)^(m-1).

%H Seiichi Manyama, <a href="/A345646/b345646.txt">Table of n, a(n) for n = 0..279</a>

%F a(n) ~ 2^(12*n) / (Pi*n)^3.

%t Table[Sum[(4*n)! / (k! * (n-k)!)^4, {k, 0, n}], {n, 0, 15}]

%Y Column 4 of A306641.

%Y Cf. A306642, A306644.

%K nonn

%O 0,2

%A _Vaclav Kotesovec_, Jun 21 2021

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 22 06:14 EDT 2024. Contains 375356 sequences. (Running on oeis4.)