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.

A269220 Number of 7Xn 0..3 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling three exactly once.

Table of values

n a(n)
1 0
2 7375872
3 2039727744
4 599456856000
5 163535201141376
6 43468685827935816
7 11273191243423937904
8 2872961996154823592256
9 722010748558146090563664
10 179436639887553691981747008
11 44187481124719769649267286128

List of values

[0, 7375872, 2039727744, 599456856000, 163535201141376, 43468685827935816, 11273191243423937904, 2872961996154823592256, 722010748558146090563664, 179436639887553691981747008, 44187481124719769649267286128]

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

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