A189804 - cp's OEIS frontend

A189804 Triangle read by rows: T(n,k) is the number of compositions of set {1, 2, ..., k} into exactly n blocks, each of size 1, 2 or 3 (n >= 0, 0 <= k <= 3*n).

n	a(n)
0	1
1	0
2	1
3	1
4	1
5	0
6	0
7	2
8	6
9	14
10	20
11	20
12	0
13	0
14	0
15	6
16	36
17	150
18	450
19	1050
20	1680
21	1680
22	0
23	0
24	0
25	0
26	24
27	240
28	1560
29	7560
30	29400
31	90720
32	218400
33	369600
34	369600
35	0
36	0
37	0
38	0
39	0
40	120
41	1800
42	16800
43	117600
44	667800
45	3137400
46	12243000
47	38808000
48	96096000
49	168168000
50	168168000

[1, 0, 1, 1, 1, 0, 0, 2, 6, 14, 20, 20, 0, 0, 0, 6, 36, 150, 450, 1050, 1680, 1680, 0, 0, 0, 0, 24, 240, 1560, 7560, 29400, 90720, 218400, 369600, 369600, 0, 0, 0, 0, 0, 120, 1800, 16800, 117600, 667800, 3137400, 12243000, 38808000, 96096000, 168168000, 168168000]

cp's OEIS Frontend

A189804 Triangle read by rows: T(n,k) is the number of compositions of set {1, 2, ..., k} into exactly n blocks, each of size 1, 2 or 3 (n >= 0, 0 <= k <= 3*n).

Table of values

List of values