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.

A253194 Number of ways to place non-intersecting diagonals in a convex (n+2)-gon so as to create no pentagons.

Table of values

n a(n)
1 1
2 3
3 10
4 39
5 162
6 707
7 3190
8 14766
9 69719
10 334481
11 1625846
12 7989908
13 39631204
14 198151579
15 997623275
16 5053274850
17 25734158411
18 131680565544
19 676693557574
20 3490897656337
21 18071699948492
22 93851485181749
23 488815126122166

List of values

[1, 3, 10, 39, 162, 707, 3190, 14766, 69719, 334481, 1625846, 7989908, 39631204, 198151579, 997623275, 5053274850, 25734158411, 131680565544, 676693557574, 3490897656337, 18071699948492, 93851485181749, 488815126122166]

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

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