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.

A217290 Integers n such that 2*cos(2*Pi/n) is an integer.

Table of values

n a(n)
0 -6
1 -4
2 -3
3 -2
4 -1
5 1
6 2
7 3
8 4
9 6

List of values

[-6, -4, -3, -2, -1, 1, 2, 3, 4, 6]