A note on r-equitable k-colorings of trees
Alain Hertz, Bernard Ries · Yugoslav journal of operations research · 2013
A graph G = (V;E) is r-equitably k-colorable if there exists a partition of V into k independent sets V1, V2,... Vk such that ||Vi|- |Vj|| ? r for all i,j ? {1,2... k}. In this note, we show that if two trees T1 and T2 of order at least two are r-equitably k-colorable for r ? 1 and k ? 3, then all trees obtained by adding an arbitrary edge between T1 and T2 are also r-equitably k-colorable.