Gordon Royle
Published 2016-11-07Version 1
This note exhibits graphs whose chromatic polynomials have the Beraha number $B_{10} = (5 + \sqrt{5})/2$ as a root. It was previously known that no other non-integer Beraha number is a chromatic root, and so these examples complete the determination of precisely which Beraha numbers can be chromatic roots.
Polynomials related to chromatic polynomials
On the imaginary parts of chromatic root
On the chromatic roots of generalized theta graphs
![QR code for arXiv:1611.01941 [math.CO]](http://oss.arxitics.com/images/favicon.svg)