A220222 - cp's OEIS frontend

A220222 Triangular array read by rows. T(n,k) is the number of functional digraphs on {1,2,...,n} such that no node is at a distance greater than one from a cycle and there are k recurrent elements whose preimage contains only one element, n>=0, 0<=k<=n.

n	a(n)
0	1
1	0
2	1
3	2
4	0
5	2
6	3
7	12
8	0
9	6
10	28
11	24
12	72
13	0
14	24
15	125
16	400
17	180
18	480
19	0
20	120
21	1146
22	2220
23	4680
24	1440
25	3600
26	0
27	720
28	8827
29	29064
30	30870
31	53760
32	12600
33	30240
34	0
35	5040
36	94200
37	272272
38	545328
39	409920
40	638400
41	120960
42	282240
43	0
44	40320
45	1007001
46	3722688
47	5989032
48	9386496
49	5518800
50	7983360
51	1270080
52	2903040
53	0
54	362880

[1, 0, 1, 2, 0, 2, 3, 12, 0, 6, 28, 24, 72, 0, 24, 125, 400, 180, 480, 0, 120, 1146, 2220, 4680, 1440, 3600, 0, 720, 8827, 29064, 30870, 53760, 12600, 30240, 0, 5040, 94200, 272272, 545328, 409920, 638400, 120960, 282240, 0, 40320, 1007001, 3722688, 5989032, 9386496, 5518800, 7983360, 1270080, 2903040, 0, 362880]

cp's OEIS Frontend

A220222 Triangular array read by rows. T(n,k) is the number of functional digraphs on {1,2,...,n} such that no node is at a distance greater than one from a cycle and there are k recurrent elements whose preimage contains only one element, n>=0, 0<=k<=n.

Table of values

List of values