The $e$-positivity of the chromatic symmetric function for twinned paths
and cycles
The $e$-positivity of the chromatic symmetric function for twinned paths
and cycles
The operation of twinning a graph at a vertex was introduced by Foley, Ho\`ang, and Merkel (2019), who conjectured that twinning preserves $e$-positivity of the chromatic symmetric function. A counterexample to this conjecture was given by Li, Li, Wang, and Yang (2021). In this paper, we prove that $e$-positivity is …