Fig. 2From: Chained graphs and some applicationsExample 2: chained graph with vertices \(v_1\), \(v_2\), and \(v_3\). The initial vertex set in (a) is \({{\mathcal{V}}}_1=\{v_1\}\), while the initial vertex set in (b) is \({{\mathcal{V}}}_1=\{v_2\}\)Back to article page