A216971 - cp's OEIS frontend

A216971 Triangle read by rows: T(n,k) is the number of functions f:{1,2,...,n}->{1,2,...,n} that have exactly k nonrecurrent elements mapped to some (one or more) recurrent element. n >= 1, 0 <= k <= n-1.

n	a(n)
1	1
2	2
3	2
4	6
5	18
6	3
7	24
8	156
9	72
10	4
11	120
12	1520
13	1260
14	220
15	5
16	720
17	17310
18	21000
19	7020
20	600
21	6
22	5040
23	232932
24	363720
25	187320
26	32970
27	1554
28	7
29	40320
30	3698744
31	6794256
32	4746840
33	1351840
34	141288
35	3920
36	8
37	362880
38	68680656
39	139241088
40	121105152
41	48822480
42	8625456
43	573048
44	9720
45	9
46	3628800
47	1471193370

[1, 2, 2, 6, 18, 3, 24, 156, 72, 4, 120, 1520, 1260, 220, 5, 720, 17310, 21000, 7020, 600, 6, 5040, 232932, 363720, 187320, 32970, 1554, 7, 40320, 3698744, 6794256, 4746840, 1351840, 141288, 3920, 8, 362880, 68680656, 139241088, 121105152, 48822480, 8625456, 573048, 9720, 9, 3628800, 1471193370]

cp's OEIS Frontend

A216971 Triangle read by rows: T(n,k) is the number of functions f:{1,2,...,n}->{1,2,...,n} that have exactly k nonrecurrent elements mapped to some (one or more) recurrent element. n >= 1, 0 <= k <= n-1.

Table of values

List of values