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.

A220830 Number of unrooted binary leaf-multi-labeled trees with n leaves on the label set [3], with each label used at least once.

Table of values

n a(n)
1 0
2 0
3 1
4 6
5 30
6 140
7 663
8 3186
9 15642
10 78441
11 400842
12 2084698
13 11009358
14 58955139
15 319619706
16 1752122667
17 9700923252
18 54194387085
19 305216395077
20 1731579241287
21 9889280682948
22 56822058078669
23 328300135291659
24 1906449141877331
25 11122447670117451
26 65168427936552522

List of values

[0, 0, 1, 6, 30, 140, 663, 3186, 15642, 78441, 400842, 2084698, 11009358, 58955139, 319619706, 1752122667, 9700923252, 54194387085, 305216395077, 1731579241287, 9889280682948, 56822058078669, 328300135291659, 1906449141877331, 11122447670117451, 65168427936552522]

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

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