A143362 - cp's OEIS frontend

A143362 Triangle read by rows: T(n,k) is the number of ordered trees with n edges and k protected vertices (0<=k<=n-1). A protected vertex in an ordered tree is a vertex at least 2 edges away from its leaf descendants.

n	a(n)
1	1
2	1
3	1
4	3
5	1
6	1
7	6
8	6
9	1
10	1
11	17
12	13
13	10
14	1
15	1
16	43
17	50
18	22
19	15
20	1
21	1
22	123
23	141
24	109
25	33
26	21
27	1
28	1
29	343
30	481
31	325
32	205
33	46
34	28
35	1
36	1
37	1004
38	1491
39	1286
40	631
41	351
42	61
43	36
44	1
45	1
46	2938
47	4929
48	4280
49	2861
50	1101
51	562
52	78
53	45
54	1
55	1
56	8791
57	15840
58	15662
59	10025
60	5676
61	1783
62	855
63	97

[1, 1, 1, 3, 1, 1, 6, 6, 1, 1, 17, 13, 10, 1, 1, 43, 50, 22, 15, 1, 1, 123, 141, 109, 33, 21, 1, 1, 343, 481, 325, 205, 46, 28, 1, 1, 1004, 1491, 1286, 631, 351, 61, 36, 1, 1, 2938, 4929, 4280, 2861, 1101, 562, 78, 45, 1, 1, 8791, 15840, 15662, 10025, 5676, 1783, 855, 97]

cp's OEIS Frontend

A143362 Triangle read by rows: T(n,k) is the number of ordered trees with n edges and k protected vertices (0<=k<=n-1). A protected vertex in an ordered tree is a vertex at least 2 edges away from its leaf descendants.

Table of values

List of values