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.

A268734 Number of n X n binary arrays with some 1 horizontally or vertically adjacent to some other 1 exactly once.

Table of values

n a(n)
1 0
2 4
3 80
4 2876
5 200204
6 29134076
7 9039552112
8 6084192150856
9 8965720251221240
10 29122359898196696856
11 209490003763160695865576
12 3348908247850171650090422060
13 119286836904111393911302107179212

List of values

[0, 4, 80, 2876, 200204, 29134076, 9039552112, 6084192150856, 8965720251221240, 29122359898196696856, 209490003763160695865576, 3348908247850171650090422060, 119286836904111393911302107179212]

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

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