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.

A220828 Number of unrooted binary leaf-multi-labeled trees with n leaves on the label set [4].

Table of values

n a(n)
1 4
2 10
3 20
4 55
5 220
6 1040
7 5480
8 31420
9 190360
10 1202930
11 7848720
12 52543935
13 359182620
14 2498614620
15 17640615900
16 126142316865
17 912047139460
18 6658803466730
19 49035674140240
20 363881247076930
21 2718918248334300
22 20442286928323170
23 154564065790535680
24 1174669811887063830

List of values

[4, 10, 20, 55, 220, 1040, 5480, 31420, 190360, 1202930, 7848720, 52543935, 359182620, 2498614620, 17640615900, 126142316865, 912047139460, 6658803466730, 49035674140240, 363881247076930, 2718918248334300, 20442286928323170, 154564065790535680, 1174669811887063830]

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

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