It turns out that the Alcuin number of a graph is closely related to the size of a minimum vertex cover in the graph, and we unravel several surprising connections between these two graph parameters.

Recently, a research team from Hokkaido University made significant progress in the complexity study of the Hitting Geodesic Intervals (HGI) problem. The HGI problem aims to find a small set of ...

Abstract The adjacent vertex-distinguishing total chromatic number of a graph 𝐺, denoted by χ𝑎𝑡 (𝐺), is the smallest denoted by 𝑘 for which 𝐺 has a proper total 𝑘-coloring such that any two ...

If k > 0, the vertex is a minimum turning point If k < 0, the vertex is a maximum turning point We can identify these properties from a quadratics graph or equation.