A264869 - cp's OEIS frontend

A264869 Triangular array: For n >= 2 and 0 <= k <= n - 2, T(n, k) equals the number of rooted duplication trees on n gene segments whose leftmost visible duplication event is (k, r), for 1 <= r <= (n - k)/2.

n	a(n)
2	1
3	1
4	1
5	2
6	2
7	2
8	4
9	6
10	6
11	6
12	10
13	16
14	22
15	22
16	22
17	26
18	48
19	70
20	92
21	92
22	92
23	74
24	144
25	236
26	328
27	420
28	420
29	420
30	218
31	454
32	782
33	1202
34	1622
35	2042
36	2042
37	2042
38	672
39	1454
40	2656
41	4278
42	6320
43	8362
44	10404
45	10404
46	10404
47	2126
48	4782
49	9060
50	15380
51	23742
52	34146
53	44550
54	54954
55	54954
56	54954

[1, 1, 1, 2, 2, 2, 4, 6, 6, 6, 10, 16, 22, 22, 22, 26, 48, 70, 92, 92, 92, 74, 144, 236, 328, 420, 420, 420, 218, 454, 782, 1202, 1622, 2042, 2042, 2042, 672, 1454, 2656, 4278, 6320, 8362, 10404, 10404, 10404, 2126, 4782, 9060, 15380, 23742, 34146, 44550, 54954, 54954, 54954]

cp's OEIS Frontend

A264869 Triangular array: For n >= 2 and 0 <= k <= n - 2, T(n, k) equals the number of rooted duplication trees on n gene segments whose leftmost visible duplication event is (k, r), for 1 <= r <= (n - k)/2.

Table of values

List of values