Some Applications of Spanning Trees in \(K_{s,t}\)

We partition the set of spanning trees contained in the complete graph \( K_n \) into spanning trees contained in the complete bipartite graph \( K_{s,t} \). This classification shows that some properties of spanning trees in \( K_n \) can be derived from trees in \( K_{s,t} \). We use Abel’s binomial theorem and the formula for spanning trees in \( K_{s,t} \) to obtain a proof of Cayley’s theorem using partial derivatives. Some results concerning non-isomorphic spanning trees are presented. In particular, we count these trees for \( Q_3 \) and the Petersen graph.