A120945 - cp's OEIS frontend

A120945 Triangle T(n,k) of number of labeled directed multigraphs (with loops), without isolated vertices, with n arrows and k vertices (n = 1,2,.., k = 1..2*n).

n	a(n)
1	1
2	2
3	1
4	8
5	18
6	12
7	1
8	18
9	108
10	272
11	300
12	120
13	1
14	33
15	393
16	2102
17	5700
18	8160
19	5880
20	1680
21	1
22	54
23	1122
24	10688
25	53550
26	153132
27	258720
28	255360
29	136080
30	30240
31	1
32	82
33	2754
34	42752
35	351650
36	1688892
37	5025832
38	9540272
39	11566800
40	8668800
41	3659040
42	665280

[1, 2, 1, 8, 18, 12, 1, 18, 108, 272, 300, 120, 1, 33, 393, 2102, 5700, 8160, 5880, 1680, 1, 54, 1122, 10688, 53550, 153132, 258720, 255360, 136080, 30240, 1, 82, 2754, 42752, 351650, 1688892, 5025832, 9540272, 11566800, 8668800, 3659040, 665280]

cp's OEIS Frontend

A120945 Triangle T(n,k) of number of labeled directed multigraphs (with loops), without isolated vertices, with n arrows and k vertices (n = 1,2,.., k = 1..2*n).

Table of values

List of values