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.

A153366 Number of zig-zag paths from top to bottom of a rectangle of width 9 with 2*n-1 rows whose color is that of the top right corner.

Table of values

n a(n)
1 5
2 16
3 56
4 200
5 720
6 2600
7 9400
8 34000
9 123000
10 445000
11 1610000
12 5825000
13 21075000
14 76250000
15 275875000
16 998125000
17 3611250000
18 13065625000
19 47271875000
20 171031250000
21 618796875000
22 2238828125000
23 8100156250000
24 29306640625000

List of values

[5, 16, 56, 200, 720, 2600, 9400, 34000, 123000, 445000, 1610000, 5825000, 21075000, 76250000, 275875000, 998125000, 3611250000, 13065625000, 47271875000, 171031250000, 618796875000, 2238828125000, 8100156250000, 29306640625000]

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

Content is available under The OEIS End-User License Agreement.