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.

A208122 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically.

Table of values

n a(n)
1 20
2 400
3 1260
4 3969
5 34713
6 303601
7 1432600
8 6760000
9 45648200
10 308248249
11 1680152229
12 9157915809
13 56635398540
14 350250912400
15 2009057864020
16 11524062773521
17 69120684953057
18 414582008296369
19 2421339816495600

List of values

[20, 400, 1260, 3969, 34713, 303601, 1432600, 6760000, 45648200, 308248249, 1680152229, 9157915809, 56635398540, 350250912400, 2009057864020, 11524062773521, 69120684953057, 414582008296369, 2421339816495600]

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

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