A201640 - cp's OEIS frontend

A201640 a(n) = Sum_{k=1..n} kbinomial(n, k)^3(n^2 + n - kn - k + k^2)/((n - k + 1)^2n).

n	a(n)
1	1
2	8
3	54
4	368
5	2550
6	17952
7	128086
8	924128
9	6729858
10	49395440
11	364979560
12	2712343680
13	20257516240
14	151957919232
15	1144281700110
16	8646263301056
17	65531851263978
18	498047725561104
19	3794627850238756
20	28976634967413920
21	221728252767064596
22	1699859618636556608

[1, 8, 54, 368, 2550, 17952, 128086, 924128, 6729858, 49395440, 364979560, 2712343680, 20257516240, 151957919232, 1144281700110, 8646263301056, 65531851263978, 498047725561104, 3794627850238756, 28976634967413920, 221728252767064596, 1699859618636556608]

cp's OEIS Frontend

A201640 a(n) = Sum_{k=1..n} kbinomial(n, k)^3(n^2 + n - kn - k + k^2)/((n - k + 1)^2n).

Table of values

List of values

cp's OEIS Frontend

A201640 a(n) = Sum_{k=1..n} k*binomial(n, k)^3*(n^2 + n - k*n - k + k^2)/((n - k + 1)^2*n).

Table of values

List of values

A201640 a(n) = Sum_{k=1..n} kbinomial(n, k)^3(n^2 + n - kn - k + k^2)/((n - k + 1)^2n).