A145855 - cp's OEIS frontend

A145855 Number of n-element subsets of {1,2,...,2n-1} whose elements sum to a multiple of n.

n	a(n)
1	1
2	1
3	4
4	9
5	26
6	76
7	246
8	809
9	2704
10	9226
11	32066
12	112716
13	400024
14	1432614
15	5170604
16	18784169
17	68635478
18	252085792
19	930138522
20	3446167834
21	12815663844
22	47820414962
23	178987624514
24	671825133644
25	2528212128776
26	9536894664376

[1, 1, 4, 9, 26, 76, 246, 809, 2704, 9226, 32066, 112716, 400024, 1432614, 5170604, 18784169, 68635478, 252085792, 930138522, 3446167834, 12815663844, 47820414962, 178987624514, 671825133644, 2528212128776, 9536894664376]

cp's OEIS Frontend

A145855 Number of n-element subsets of {1,2,...,2n-1} whose elements sum to a multiple of n.

Table of values

List of values