A383274 - cp's OEIS frontend

A383274 a(n) = Sum_{i,j = 0..n} C(n, i)^2C(n, j)^2C(i+j, i)*2^(i+j).

n	a(n)
0	1
1	13
2	441
3	20629
4	1119361
5	66116013
6	4126228569
7	267666251733
8	17868312820737
9	1219477111897933
10	84701899713767161
11	5967906378862013973
12	425503428034568158081
13	30642774518964618986989
14	2225692868157573335052441
15	162858794856607965831417429
16	11993850186156155815298686977

[1, 13, 441, 20629, 1119361, 66116013, 4126228569, 267666251733, 17868312820737, 1219477111897933, 84701899713767161, 5967906378862013973, 425503428034568158081, 30642774518964618986989, 2225692868157573335052441, 162858794856607965831417429, 11993850186156155815298686977]

cp's OEIS Frontend

A383274 a(n) = Sum_{i,j = 0..n} C(n, i)^2C(n, j)^2C(i+j, i)*2^(i+j).

Table of values

List of values

cp's OEIS Frontend

A383274 a(n) = Sum_{i,j = 0..n} C(n, i)^2*C(n, j)^2*C(i+j, i)*2^(i+j).

Table of values

List of values

A383274 a(n) = Sum_{i,j = 0..n} C(n, i)^2C(n, j)^2C(i+j, i)*2^(i+j).