Equitable Colorings of $K\mathrm{\_}4$-minor-free Graphs

We demonstrate that for every positive integer $\mathrm{\Delta }$, every K_4-minor-free graph with maximum degree $\mathrm{\Delta }$ admits an equitable coloring with k colors wherek $\ge$ ($\mathrm{\Delta }$+3)/2. This bound is tight and confirms a conjecture by Zhang and Whu. We do not use the discharging method but rather exploit decomposition trees of K 4-minor-free graphs.