A259335 - cp's OEIS frontend

A259335 a(n) = ( Sum_{k=0..n} binomial(2n, k)^2 (binomial(2n, k+1) - binomial(2n, k-1)) )/(nbinomial(2n, n)).

n	a(n)
1	1
2	7
3	61
4	611
5	6686
6	77729
7	944245
8	11859355
9	152893720
10	2013070126
11	26967817306
12	366542344117
13	5043651762826
14	70138959074461
15	984384594022117
16	13927418363218955
17	198459156018467084
18	2845950809029225472
19	41044332341739034032
20	594983281327999736694

[1, 7, 61, 611, 6686, 77729, 944245, 11859355, 152893720, 2013070126, 26967817306, 366542344117, 5043651762826, 70138959074461, 984384594022117, 13927418363218955, 198459156018467084, 2845950809029225472, 41044332341739034032, 594983281327999736694]

cp's OEIS Frontend

A259335 a(n) = ( Sum_{k=0..n} binomial(2n, k)^2 (binomial(2n, k+1) - binomial(2n, k-1)) )/(nbinomial(2n, n)).

Table of values

List of values

cp's OEIS Frontend

A259335 a(n) = ( Sum_{k=0..n} binomial(2*n, k)^2 * (binomial(2*n, k+1) - binomial(2*n, k-1)) )/(n*binomial(2*n, n)).

Table of values

List of values

A259335 a(n) = ( Sum_{k=0..n} binomial(2n, k)^2 (binomial(2n, k+1) - binomial(2n, k-1)) )/(nbinomial(2n, n)).