A336309 - cp's OEIS frontend

A336309 Triangular array read by rows. T(n,k) is the number of labeled rooted unordered binary trees (as in A036774) with path length exactly k, n >= 1, 0 <= k <= C(n,2).

n	a(n)
1	1
2	0
3	2
4	0
5	0
6	3
7	6
8	0
9	0
10	0
11	0
12	24
13	12
14	24
15	0
16	0
17	0
18	0
19	0
20	0
21	120
22	120
23	120
24	60
25	120
26	0
27	0
28	0
29	0
30	0
31	0
32	0
33	0
34	360
35	1440
36	360
37	1440
38	720
39	720
40	360
41	720
42	0
43	0
44	0
45	0
46	0
47	0
48	0
49	0
50	0
51	0
52	630
53	7560
54	10080
55	10080
56	7560
57	12600
58	7560
59	10080
60	5040
61	5040
62	2520
63	5040

[1, 0, 2, 0, 0, 3, 6, 0, 0, 0, 0, 24, 12, 24, 0, 0, 0, 0, 0, 0, 120, 120, 120, 60, 120, 0, 0, 0, 0, 0, 0, 0, 0, 360, 1440, 360, 1440, 720, 720, 360, 720, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 630, 7560, 10080, 10080, 7560, 12600, 7560, 10080, 5040, 5040, 2520, 5040]

cp's OEIS Frontend

A336309 Triangular array read by rows. T(n,k) is the number of labeled rooted unordered binary trees (as in A036774) with path length exactly k, n >= 1, 0 <= k <= C(n,2).

Table of values

List of values