A127157 - cp's OEIS frontend

A127157 Triangle read by rows: T(n,k) is the number of ordered trees with n edges and 2k nodes of odd degree (not outdegree; 1 <= k <= ceiling(n/2)).

n	a(n)
1	1
2	2
3	3
4	2
5	4
6	10
7	5
8	30
9	7
10	6
11	70
12	56
13	7
14	140
15	252
16	30
17	8
18	252
19	840
20	330
21	9
22	420
23	2310
24	1980
25	143
26	10
27	660
28	5544
29	8580
30	2002
31	11
32	990
33	12012
34	30030
35	15015
36	728
37	12
38	1430
39	24024
40	90090
41	80080
42	12376
43	13
44	2002
45	45045
46	240240
47	340340
48	111384
49	3876
50	14
51	2730

[1, 2, 3, 2, 4, 10, 5, 30, 7, 6, 70, 56, 7, 140, 252, 30, 8, 252, 840, 330, 9, 420, 2310, 1980, 143, 10, 660, 5544, 8580, 2002, 11, 990, 12012, 30030, 15015, 728, 12, 1430, 24024, 90090, 80080, 12376, 13, 2002, 45045, 240240, 340340, 111384, 3876, 14, 2730]

cp's OEIS Frontend

A127157 Triangle read by rows: T(n,k) is the number of ordered trees with n edges and 2k nodes of odd degree (not outdegree; 1 <= k <= ceiling(n/2)).

Table of values

List of values