A Note on The Vertex-Distinguishing Proper Total Coloring of Graphs.

Abstract

Let \(G\) be a simple graph of order \(p \geq 2\). A proper \(k\)-total coloring of a simple graph \(G\) is called a \(k\)-vertex distinguishing proper total coloring (\(k\)-VDTC) if for any two distinct vertices \(u\) and \(v\) of \(G\), the set of colors assigned to \(u\) and its incident edges differs from the set of colors assigned to \(v\) and its incident edges. The notation \(\chi_{vt}(G)\) indicates the smallest number of colors required for which \(G\) admits a \(k\)-VDTC with \(k \geq \chi_{vt}(G)\). For every integer \(m \geq 3\), we will present a graph \(G\) of maximum degree \(m\) such that \(\chi_{vt}(G) < \chi_{vt}(H)\) for some proper subgraph \(H \subseteq G\).