Graphs with chromatic roots in the interval (1,2)

2007/04/18 by Gordon Royle, Royle, Gordon F.
Computer Science · Engineering · #05C15 #Advanced Graph Theory Research #Combinatorics (math.CO) #FOS: Mathematics #Graph Labeling and Dimension Problems #graph theory and CDMA systems

paper · pdf · doi:10.48550/arxiv.0704.2264

openalex publication_date 2007/04/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We present an infinite family of 3-connected non-bipartite graphs with chromatic roots in the interval (1,2) thus resolving a conjecture of Jackson's in the negative. In addition, we briefly consider other graph classes that are conjectured to have no chromatic roots in (1,2).

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