A245692 - cp's OEIS frontend

A245692 Number T(n,k) of endofunctions f on [n] that are self-inverse on [k] but not on [k+1]; triangle T(n,k), n>=0, 0<=k<=n, read by rows.

n	a(n)
0	1
1	0
2	1
3	1
4	1
5	2
6	12
7	7
8	4
9	4
10	144
11	62
12	28
13	12
14	10
15	2000
16	695
17	264
18	100
19	40
20	26
21	32400
22	9504
23	3126
24	1050
25	370
26	130
27	76
28	605052
29	154007
30	44716
31	13458
32	4256
33	1366
34	456
35	232
36	12845056
37	2891776
38	751872
39	204776
40	58784
41	17292
42	5272
43	1624
44	764

[1, 0, 1, 1, 1, 2, 12, 7, 4, 4, 144, 62, 28, 12, 10, 2000, 695, 264, 100, 40, 26, 32400, 9504, 3126, 1050, 370, 130, 76, 605052, 154007, 44716, 13458, 4256, 1366, 456, 232, 12845056, 2891776, 751872, 204776, 58784, 17292, 5272, 1624, 764]

cp's OEIS Frontend

A245692 Number T(n,k) of endofunctions f on [n] that are self-inverse on [k] but not on [k+1]; triangle T(n,k), n>=0, 0<=k<=n, read by rows.

Table of values

List of values