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.

A055531 Number of labeled order relations on n nodes in which longest chain has 2 nodes.

Table of values

n a(n)
2 2
3 12
4 86
5 840
6 11642
7 227892
8 6285806
9 243593040
10 13262556722
11 1014466283292
12 109128015915206
13 16521353903210520
14 3524056001906654762
15 1059868947134489801412
16 449831067019305308555486
17 269568708630308018001547680
18 228228540531327778410439620962

List of values

[2, 12, 86, 840, 11642, 227892, 6285806, 243593040, 13262556722, 1014466283292, 109128015915206, 16521353903210520, 3524056001906654762, 1059868947134489801412, 449831067019305308555486, 269568708630308018001547680, 228228540531327778410439620962]

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

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