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.

A026641 Number of nodes of even outdegree (including leaves) in all ordered trees with n edges.

Table of values

n a(n)
0 1
1 1
2 4
3 13
4 46
5 166
6 610
7 2269
8 8518
9 32206
10 122464
11 467842
12 1794196
13 6903352
14 26635774
15 103020253
16 399300166
17 1550554582
18 6031074184
19 23493410758
20 91638191236
21 357874310212
22 1399137067684
23 5475504511858
24 21447950506396

List of values

[1, 1, 4, 13, 46, 166, 610, 2269, 8518, 32206, 122464, 467842, 1794196, 6903352, 26635774, 103020253, 399300166, 1550554582, 6031074184, 23493410758, 91638191236, 357874310212, 1399137067684, 5475504511858, 21447950506396]