A219859 - cp's OEIS frontend

A219859 Triangular array read by rows: T(n,k) is the number of endofunctions, functions f:{1,2,...,n}->{1,2,...,n}, that have exactly k elements with no preimage; n>=0, 0<=k<=n.

n	a(n)
0	1
1	1
2	0
3	2
4	2
5	0
6	6
7	18
8	3
9	0
10	24
11	144
12	84
13	4
14	0
15	120
16	1200
17	1500
18	300
19	5
20	0
21	720
22	10800
23	23400
24	10800
25	930
26	6
27	0
28	5040
29	105840
30	352800
31	294000
32	63210
33	2646
34	7
35	0
36	40320
37	1128960
38	5362560
39	7056000
40	2857680
41	324576
42	7112
43	8
44	0
45	362880
46	13063680
47	83825280
48	160030080
49	105099120
50	23496480
51	1524600
52	18360
53	9
54	0

[1, 1, 0, 2, 2, 0, 6, 18, 3, 0, 24, 144, 84, 4, 0, 120, 1200, 1500, 300, 5, 0, 720, 10800, 23400, 10800, 930, 6, 0, 5040, 105840, 352800, 294000, 63210, 2646, 7, 0, 40320, 1128960, 5362560, 7056000, 2857680, 324576, 7112, 8, 0, 362880, 13063680, 83825280, 160030080, 105099120, 23496480, 1524600, 18360, 9, 0]

cp's OEIS Frontend

A219859 Triangular array read by rows: T(n,k) is the number of endofunctions, functions f:{1,2,...,n}->{1,2,...,n}, that have exactly k elements with no preimage; n>=0, 0<=k<=n.

Table of values

List of values