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.

A320271 Number of unlabeled semi-binary rooted trees with n nodes in which the non-leaf branches directly under any given node are all equal.

Table of values

n a(n)
1 1
2 1
3 2
4 3
5 6
6 9
7 17
8 26
9 46
10 72
11 124
12 196
13 329
14 525
15 871
16 1396
17 2293
18 3689
19 6028
20 9717
21 15817
22 25534
23 41475
24 67009
25 108680
26 175689
27 284698
28 460387
29 745610
30 1205997
31 1952478
32 3158475
33 5112349
34 8270824
35 13385466
36 21656290
37 35045445
38 56701735
39 91753208

List of values

[1, 1, 2, 3, 6, 9, 17, 26, 46, 72, 124, 196, 329, 525, 871, 1396, 2293, 3689, 6028, 9717, 15817, 25534, 41475, 67009, 108680, 175689, 284698, 460387, 745610, 1205997, 1952478, 3158475, 5112349, 8270824, 13385466, 21656290, 35045445, 56701735, 91753208]

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

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