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.

A143889 Number of ways of placing kings with no more than 4 mutual attacks on an n X n chessboard symmetric about main diagonal.

Table of values

n a(n)
0 1
1 2
2 7
3 33
4 202
5 1671
6 17279
7 234724
8 4081665
9 92343898
10 2711730350
11 103991393887
12 5218390436191

List of values

[1, 2, 7, 33, 202, 1671, 17279, 234724, 4081665, 92343898, 2711730350, 103991393887, 5218390436191]