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.

A127540 Number of odd-length branches starting at the root in all ordered trees with n edges.

Table of values

n a(n)
0 0
1 1
2 2
3 7
4 21
5 69
6 228
7 773
8 2659
9 9275
10 32715
11 116511
12 418377
13 1513163
14 5507242
15 20155583
16 74131537
17 273862373
18 1015762117
19 3781095113
20 14121051487
21 52895245133
22 198681804877
23 748162728797
24 2823879525331
25 10681527145369

List of values

[0, 1, 2, 7, 21, 69, 228, 773, 2659, 9275, 32715, 116511, 418377, 1513163, 5507242, 20155583, 74131537, 273862373, 1015762117, 3781095113, 14121051487, 52895245133, 198681804877, 748162728797, 2823879525331, 10681527145369]

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

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