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.

A000957 Fine's sequence (or Fine numbers): number of relations of valence >= 1 on an n-set; also number of ordered rooted trees with n nodes having root of even degree.

Table of values

n a(n)
0 0
1 1
2 0
3 1
4 2
5 6
6 18
7 57
8 186
9 622
10 2120
11 7338
12 25724
13 91144
14 325878
15 1174281
16 4260282
17 15548694
18 57048048
19 210295326
20 778483932
21 2892818244
22 10786724388
23 40347919626
24 151355847012
25 569274150156
26 2146336125648
27 8110508473252
28 30711521221376

List of values

[0, 1, 0, 1, 2, 6, 18, 57, 186, 622, 2120, 7338, 25724, 91144, 325878, 1174281, 4260282, 15548694, 57048048, 210295326, 778483932, 2892818244, 10786724388, 40347919626, 151355847012, 569274150156, 2146336125648, 8110508473252, 30711521221376]

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

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