A130809 - cp's OEIS frontend

A130809 If X_1, ..., X_n is a partition of a 2n-set X into 2-blocks then a(n) is equal to the number of 3-subsets of X containing none of X_i, (i=1,...,n).

n	a(n)
3	8
4	32
5	80
6	160
7	280
8	448
9	672
10	960
11	1320
12	1760
13	2288
14	2912
15	3640
16	4480
17	5440
18	6528
19	7752
20	9120
21	10640
22	12320
23	14168
24	16192
25	18400
26	20800
27	23400
28	26208
29	29232
30	32480
31	35960
32	39680
33	43648
34	47872
35	52360
36	57120
37	62160
38	67488
39	73112
40	79040
41	85280

[8, 32, 80, 160, 280, 448, 672, 960, 1320, 1760, 2288, 2912, 3640, 4480, 5440, 6528, 7752, 9120, 10640, 12320, 14168, 16192, 18400, 20800, 23400, 26208, 29232, 32480, 35960, 39680, 43648, 47872, 52360, 57120, 62160, 67488, 73112, 79040, 85280]

cp's OEIS Frontend

A130809 If X_1, ..., X_n is a partition of a 2n-set X into 2-blocks then a(n) is equal to the number of 3-subsets of X containing none of X_i, (i=1,...,n).

Table of values

List of values