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.

A223911 Number of tiered orders on n nodes (corrected version of A006860).

Table of values

n a(n)
0 1
1 1
2 3
3 13
4 111
5 1381
6 25623
7 678133
8 26169951
9 1447456261
10 114973232583
11 13034314621813
12 2103826463800911
13 481932523110975301
14 156356753093586913143
15 71729530379673590609653
16 46471511649877647638694591
17 42487759521494442057018000901
18 54781291469300608901184153800103

List of values

[1, 1, 3, 13, 111, 1381, 25623, 678133, 26169951, 1447456261, 114973232583, 13034314621813, 2103826463800911, 481932523110975301, 156356753093586913143, 71729530379673590609653, 46471511649877647638694591, 42487759521494442057018000901, 54781291469300608901184153800103]

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

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