Proof of a conjecture of Bowlin and Brin on four-colouring triangulations

Abstract We prove a conjecture of Bowlin and Brin that for all n ≥ 5, the n-vertex biwheel is the planar triangulation with n vertices admitting the largest number of four-colourings

Proof of a conjecture of Bowlin and Brin on four-colouring triangulations

We prove a conjecture of Bowlin and Brin that for all n >= 5, the n-vertex biwheel is the planar triangulation with n vertices admitting the largest number of four-colourings. (C) 2013 Elsevier Ltd. All rights reserved