A330088 - cp's OEIS frontend

A330088 a(n) = Sum_{k=1..n} binomial(n,k) * sigma(k) * sigma(n - k + 1), where sigma = A000203.

n	a(n)
1	1
2	9
3	43
4	155
5	511
6	1442
7	4131
8	10323
9	28171
10	63987
11	171667
12	369395
13	957958
14	2047694
15	5078963
16	10671529
17	26542339
18	53522031
19	132273403
20	268623854
21	647842889
22	1266118858
23	3197923083
24	6058756355
25	14581380971
26	29480406552
27	68634048862
28	131847974143
29	323289015466
30	611887749996

[1, 9, 43, 155, 511, 1442, 4131, 10323, 28171, 63987, 171667, 369395, 957958, 2047694, 5078963, 10671529, 26542339, 53522031, 132273403, 268623854, 647842889, 1266118858, 3197923083, 6058756355, 14581380971, 29480406552, 68634048862, 131847974143, 323289015466, 611887749996]

cp's OEIS Frontend

A330088 a(n) = Sum_{k=1..n} binomial(n,k) * sigma(k) * sigma(n - k + 1), where sigma = A000203.

Table of values

List of values