A284417 - cp's OEIS frontend

A284417 Triangular array read by rows. T(n,k) is the number of rooted labeled trees on n nodes with exactly k vertices whose unique descendent is a leaf, n >= 1, 0 <= k <= floor((n-1)/2) + delta_{2,n}.

n	a(n)
1	1
2	0
3	2
4	3
5	6
6	16
7	48
8	145
9	420
10	60
11	1536
12	4800
13	1440
14	19579
15	65730
16	31500
17	840
18	290816
19	1053696
20	698880
21	53760
22	4942305
23	19332936
24	16367400
25	2388960
26	15120
27	94689280
28	399052800
29	410296320
30	93542400
31	2419200
32	2020278931
33	9146127870
34	11044008360
35	3526261200
36	200415600
37	332640
38	47523053568
39	230339788800
40	319018106880
41	133013422080
42	12986265600
43	127733760

[1, 0, 2, 3, 6, 16, 48, 145, 420, 60, 1536, 4800, 1440, 19579, 65730, 31500, 840, 290816, 1053696, 698880, 53760, 4942305, 19332936, 16367400, 2388960, 15120, 94689280, 399052800, 410296320, 93542400, 2419200, 2020278931, 9146127870, 11044008360, 3526261200, 200415600, 332640, 47523053568, 230339788800, 319018106880, 133013422080, 12986265600, 127733760]

cp's OEIS Frontend

A284417 Triangular array read by rows. T(n,k) is the number of rooted labeled trees on n nodes with exactly k vertices whose unique descendent is a leaf, n >= 1, 0 <= k <= floor((n-1)/2) + delta_{2,n}.

Table of values

List of values