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.

A054515 Number of ways to place non-intersecting diagonals in convex (n+2)-gon so as to create no quadrilaterals.

Table of values

n a(n)
0 1
1 1
2 2
3 6
4 21
5 78
6 301
7 1198
8 4888
9 20340
10 85986
11 368239
12 1594183
13 6965380
14 30675399
15 136026759
16 606848034
17 2721783023
18 12265670909
19 55511013680
20 252193872912
21 1149742659556
22 5258257323304
23 24117924005616
24 110915268468358
25 511334146237807
26 2362650323603539

List of values

[1, 1, 2, 6, 21, 78, 301, 1198, 4888, 20340, 85986, 368239, 1594183, 6965380, 30675399, 136026759, 606848034, 2721783023, 12265670909, 55511013680, 252193872912, 1149742659556, 5258257323304, 24117924005616, 110915268468358, 511334146237807, 2362650323603539]

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

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