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.

A197273 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 2,0,1,1,1 for x=0,1,2,3,4.

Table of values

n a(n)
1 1
2 9
3 34
4 627
5 16890
6 1276986
7 209785488
8 84453386767
9 71088592371829

List of values

[1, 9, 34, 627, 16890, 1276986, 209785488, 84453386767, 71088592371829]