cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A109186 Number of hierarchical orderings of n unlabeled elements where levels are clustered. Labeled analog of A104525.

Table of values

n a(n)
1 1
2 5
3 36
4 340
5 3968
6 55045
7 883578
8 16092772
9 327632793
10 7369013917
11 181373908752
12 4847134062319
13 139729893353690
14 4320778186663065
15 142630863311312977
16 5005242986601625051
17 186036975046460920033
18 7299970808014926301354
19 301529053235119043206790

List of values

[1, 5, 36, 340, 3968, 55045, 883578, 16092772, 327632793, 7369013917, 181373908752, 4847134062319, 139729893353690, 4320778186663065, 142630863311312977, 5005242986601625051, 186036975046460920033, 7299970808014926301354, 301529053235119043206790]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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