A075729 - cp's OEIS frontend

A075729 Number of different hierarchical orderings that can be formed from n labeled elements: these are divided into groups and the elements in each group are then arranged in a "preferential arrangement" or "weak order" as in A000670.

n	a(n)
0	1
1	1
2	4
3	23
4	173
5	1602
6	17575
7	222497
8	3188806
9	50988405
10	899222457
11	17329515172
12	362164300173
13	8155216185781
14	196789115887252
15	5064722539020379
16	138457553073641465
17	4006059432756066914
18	122284085809137076203
19	3926775294104305483621
20	132313462760902116605534

[1, 1, 4, 23, 173, 1602, 17575, 222497, 3188806, 50988405, 899222457, 17329515172, 362164300173, 8155216185781, 196789115887252, 5064722539020379, 138457553073641465, 4006059432756066914, 122284085809137076203, 3926775294104305483621, 132313462760902116605534]

cp's OEIS Frontend

A075729 Number of different hierarchical orderings that can be formed from n labeled elements: these are divided into groups and the elements in each group are then arranged in a "preferential arrangement" or "weak order" as in A000670.

Table of values

List of values