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.

A282879 Number of nX2 0..1 arrays with no 1 equal to more than one of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element.

Table of values

n a(n)
1 0
2 2
3 8
4 32
5 122
6 416
7 1414
8 4626
9 14930
10 47432
11 149032
12 463918
13 1432956
14 4397436
15 13419434
16 40754026
17 123245234
18 371322718
19 1115052844
20 3338521720
21 9969125698
22 29697147320
23 88271949298
24 261856896380
25 775373941754
26 2292071140404

List of values

[0, 2, 8, 32, 122, 416, 1414, 4626, 14930, 47432, 149032, 463918, 1432956, 4397436, 13419434, 40754026, 123245234, 371322718, 1115052844, 3338521720, 9969125698, 29697147320, 88271949298, 261856896380, 775373941754, 2292071140404]

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

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