A088325 - cp's OEIS frontend

A088325 Piet Hut's "coat-hanger" sequence: unlabeled forests of rooted trees with n edges, where there can be any number of components, the outdegree of each node is <= 2 and the symmetric group acts on the components.

n	a(n)
0	1
1	1
2	2
3	4
4	8
5	16
6	34
7	71
8	153
9	332
10	730
11	1617
12	3620
13	8148
14	18473
15	42097
16	96420
17	221770
18	512133
19	1186712
20	2758707
21	6431395
22	15033320
23	35224825
24	82720273
25	194655030
26	458931973
27	1083926784
28	2564305754
29	6075896220
30	14417163975
31	34256236039
32	81499535281
33	194130771581

[1, 1, 2, 4, 8, 16, 34, 71, 153, 332, 730, 1617, 3620, 8148, 18473, 42097, 96420, 221770, 512133, 1186712, 2758707, 6431395, 15033320, 35224825, 82720273, 194655030, 458931973, 1083926784, 2564305754, 6075896220, 14417163975, 34256236039, 81499535281, 194130771581]

cp's OEIS Frontend

A088325 Piet Hut's "coat-hanger" sequence: unlabeled forests of rooted trees with n edges, where there can be any number of components, the outdegree of each node is <= 2 and the symmetric group acts on the components.

Table of values

List of values