A dichotomy for the kernel by $H$-walks problem in digraphs

Hortensia Galeana-Sánchez, César Hernández-Cruz

Let $H=(V_H,A_H)$ be a digraph which may contain loops, and let $D=(V_D,A_D)$ be a loopless digraph with a coloring of its arcs $c:A_D\to V_H$. An $H$-walk of $D$ is a walk…