On May 16, 2019, Xin Zhang (张欣) from Xidian University, China discusses various results on the equitable tree-k-coloring of graphs, a problem of partitioning the vertex set of a graph into vertex-disjoint induced subgraphs having no cycles with almost same size. The title of his talk was “On equitable tree-colorings of graphs“. Xin Zhang is visiting IBS Discrete Mathematics Group from May 15 to May 19.