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.

A030980 Number of planted noncrossing bushes with n nodes; i.e., rooted noncrossing trees with n nodes, root degree 1 and no nonroot nodes of degree 1.

Table of values

n a(n)
1 1
2 0
3 3
4 4
5 23
6 66
7 280
8 1030
9 4207
10 16852
11 69747
12 289950
13 1222540
14 5192344
15 22239672
16 95864902
17 415730735
18 1812177000
19 7936353049
20 34901789568
21 154067755503
22 682428824890
23 3032173906692
24 13510960371744
25 60360526255204
26 270311970889296
27 1213232586744900
28 5456560663318648

List of values

[1, 0, 3, 4, 23, 66, 280, 1030, 4207, 16852, 69747, 289950, 1222540, 5192344, 22239672, 95864902, 415730735, 1812177000, 7936353049, 34901789568, 154067755503, 682428824890, 3032173906692, 13510960371744, 60360526255204, 270311970889296, 1213232586744900, 5456560663318648]

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

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