A246542 - cp's OEIS frontend

A246542 a(n) = 2/n^2( sum_{k=0..n-1} (2k+1)C(n-1,k)^2C(n+k,k) ), where C(m,k) denotes the binomial coefficient m!/(k!*(m-k)!).

n	a(n)
1	2
2	5
3	22
4	132
5	918
6	6981
7	56390
8	475796
9	4149286
10	37133043
11	339307098
12	3154030050
13	29741815998
14	283896719073
15	2738445478758
16	26656533873204
17	261561469613190
18	2584718580416919
19	25703179602581234
20	257046296680889600
21	2583719988283365322
22	26090463844931102715
23	264570229302222957162
24	2693187696469413499902
25	27511970457139362253598

[2, 5, 22, 132, 918, 6981, 56390, 475796, 4149286, 37133043, 339307098, 3154030050, 29741815998, 283896719073, 2738445478758, 26656533873204, 261561469613190, 2584718580416919, 25703179602581234, 257046296680889600, 2583719988283365322, 26090463844931102715, 264570229302222957162, 2693187696469413499902, 27511970457139362253598]

cp's OEIS Frontend

A246542 a(n) = 2/n^2( sum_{k=0..n-1} (2k+1)C(n-1,k)^2C(n+k,k) ), where C(m,k) denotes the binomial coefficient m!/(k!*(m-k)!).

Table of values

List of values

cp's OEIS Frontend

A246542 a(n) = 2/n^2*( sum_{k=0..n-1} (2*k+1)*C(n-1,k)^2*C(n+k,k) ), where C(m,k) denotes the binomial coefficient m!/(k!*(m-k)!).

Table of values

List of values

A246542 a(n) = 2/n^2( sum_{k=0..n-1} (2k+1)C(n-1,k)^2C(n+k,k) ), where C(m,k) denotes the binomial coefficient m!/(k!*(m-k)!).