Mishelle Cordero

1 Introduction Let G = ( V , E ) $$ G=\left(V,E\right) $$ be an undirected graph, with V $$ V $$ and E $$ E $$ its node and edge sets, respectively. Let d : E → ℝ + $$ d:E\to {\mathbb{R}}^{+} $$ be a cost function over the set of edges. Additionally, let k ≥ 2 $$ k\ge 2 $$ and α ≥ 2 $$ \alpha \ge 2 $$ be two integer numbers.