A152684 - cp's OEIS frontend

A152684 a(n) is the number of top-down sequences (F_1, F_2, ..., F_n) whereas each F_i is a labeled forest on n nodes, containing i directed rooted trees. F_(i+1) is proper subset of F_i.

n	a(n)
1	1
2	2
3	18
4	384
5	15000
6	933120
7	84707280
8	10569646080
9	1735643790720
10	362880000000000
11	94121726392108800
12	29658516531078758400
13	11159820050604594969600
14	4942478402320838374195200
15	2544989406021562500000000000
16	1507645899890367707813511168000

[1, 2, 18, 384, 15000, 933120, 84707280, 10569646080, 1735643790720, 362880000000000, 94121726392108800, 29658516531078758400, 11159820050604594969600, 4942478402320838374195200, 2544989406021562500000000000, 1507645899890367707813511168000]

cp's OEIS Frontend

A152684 a(n) is the number of top-down sequences (F_1, F_2, ..., F_n) whereas each F_i is a labeled forest on n nodes, containing i directed rooted trees. F_(i+1) is proper subset of F_i.

Table of values

List of values