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.

A283574 Number of 3Xn 0..1 arrays with no 1 equal to more than one of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly one element.

Table of values

n a(n)
1 0
2 16
3 169
4 674
5 4313
6 21186
7 104464
8 513458
9 2431143
10 11478378
11 53471911
12 246887096
13 1132514276
14 5160569268
15 23395062541
16 105570183858
17 474452680669
18 2124725208078
19 9484785230640
20 42219767106150
21 187451695326747

List of values

[0, 16, 169, 674, 4313, 21186, 104464, 513458, 2431143, 11478378, 53471911, 246887096, 1132514276, 5160569268, 23395062541, 105570183858, 474452680669, 2124725208078, 9484785230640, 42219767106150, 187451695326747]

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

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