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!)
A104256 [ (2n-1)!!/(4n) ]. 1

%I

%S 0,0,1,6,47,433,4826,63344,957206,16368226,312484331,6588211317,

%T 152035645781,3811750833515,103171389227156,2998418499414228,

%U 93127351040630156,3078376326065274609,107905191218919625781

%N [ (2n-1)!!/(4n) ].

%C Asymptotic estimate for A054499(n).

%H A. Khruzin, <a href="http://arXiv.org/abs/math.CO/0008209">Enumeration of chord diagrams</a>

%K nonn

%O 1,4

%A _Ralf Stephan_, Mar 02 2005

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 May 29 16:43 EDT 2020. Contains 334704 sequences. (Running on oeis4.)