The complexity of spanning tree problems involving graphical indices.

We consider the computational complexity of spanning tree problems involving the graphical function-index. This index was recently introduced by Li and Peng as a unification of a long list of chemical and topological indices. We present a number of unified approaches to determine the NP -completeness and APX -completeness of maximum and minimum spanning tree problems involving this index. We give many examples of well-studied topological indices for which the associated complexity questions are covered by our results. [ABSTRACT FROM AUTHOR]