A057271 - cp's OEIS frontend

A057271 Triangle T(n,k) of number of digraphs with a source and a sink on n labeled nodes and k arcs, k=0,1,..,n*(n-1).

n	a(n)
1	1
2	0
3	2
4	1
5	0
6	0
7	6
8	20
9	15
10	6
11	1
12	0
13	0
14	0
15	24
16	234
17	672
18	908
19	792
20	495
21	220
22	66
23	12
24	1
25	0
26	0
27	0
28	0
29	120
30	2544
31	16880
32	55000
33	111225
34	161660
35	183006
36	167660
37	125945
38	77520
39	38760
40	15504
41	4845
42	1140
43	190
44	20
45	1

[1, 0, 2, 1, 0, 0, 6, 20, 15, 6, 1, 0, 0, 0, 24, 234, 672, 908, 792, 495, 220, 66, 12, 1, 0, 0, 0, 0, 120, 2544, 16880, 55000, 111225, 161660, 183006, 167660, 125945, 77520, 38760, 15504, 4845, 1140, 190, 20, 1]

cp's OEIS Frontend

A057271 Triangle T(n,k) of number of digraphs with a source and a sink on n labeled nodes and k arcs, k=0,1,..,n*(n-1).

Table of values

List of values