A384491 - cp's OEIS frontend

A384491 a(n) = n!^2 * Sum_{k=0..n} Stirling2(2k,k) Stirling2(2n-2k,n-k) / binomial(n,k)^2.

n	a(n)
0	1
1	2
2	57
3	6536
4	1966816
5	1226860992
6	1373652478656
7	2507498281198080
8	6966291361870181376
9	27969794062091821670400
10	155875927262331497576140800
11	1167389777699203314381963264000
12	11441270265465265986005655905894400
13	143525982910350708912088976768630784000

[1, 2, 57, 6536, 1966816, 1226860992, 1373652478656, 2507498281198080, 6966291361870181376, 27969794062091821670400, 155875927262331497576140800, 1167389777699203314381963264000, 11441270265465265986005655905894400, 143525982910350708912088976768630784000]

cp's OEIS Frontend

A384491 a(n) = n!^2 * Sum_{k=0..n} Stirling2(2k,k) Stirling2(2n-2k,n-k) / binomial(n,k)^2.

Table of values

List of values

cp's OEIS Frontend

A384491 a(n) = n!^2 * Sum_{k=0..n} Stirling2(2*k,k) * Stirling2(2*n-2*k,n-k) / binomial(n,k)^2.

Table of values

List of values

A384491 a(n) = n!^2 * Sum_{k=0..n} Stirling2(2k,k) Stirling2(2n-2k,n-k) / binomial(n,k)^2.