A047169 - cp's OEIS frontend

A047169 Number of nonempty subsets of {1,2,...,n} in which exactly 1/6 of the elements are <= n/2.

n	a(n)
1	0
2	0
3	0
4	0
5	0
6	0
7	0
8	0
9	4
10	5
11	30
12	36
13	126
14	147
15	392
16	448
17	1008
18	1134
19	2304
20	2565
21	5115
22	5687
23	12342
24	13860
25	34320
26	39039
27	104104
28	119119
29	315679
30	360815
31	913640
32	1039808
33	2508928
34	2842604
35	6651624
36	7515054
37	17505954
38	19773414
39	46915104
40	53093125
41	129385725
42	146794494

[0, 0, 0, 0, 0, 0, 0, 0, 4, 5, 30, 36, 126, 147, 392, 448, 1008, 1134, 2304, 2565, 5115, 5687, 12342, 13860, 34320, 39039, 104104, 119119, 315679, 360815, 913640, 1039808, 2508928, 2842604, 6651624, 7515054, 17505954, 19773414, 46915104, 53093125, 129385725, 146794494]

cp's OEIS Frontend

A047169 Number of nonempty subsets of {1,2,...,n} in which exactly 1/6 of the elements are <= n/2.

Table of values

List of values