Paths With Three Blocks In Digraphs

Maidoun Mortada, Amine El Sahili, Zahraa Mohsen

A path with three blocks $P(k,l,r)$ is an oriented path formed by $k$-forward arcs followed by $l$-backward arcs then $r$-forward arcs. We prove that any $(2k+1)$-chromatic digraph…