The number of labeled trees on n vertices equals n^{n−2}. Proved by Cayley 1889; Prüfer 1918 gave the bijection with length-(n−2) sequences over {1, …, n} that made the proof a one-liner. Core combinatorial identity connecting trees,…
The number of labeled trees on n vertices equals n^{n−2}. Proved by Cayley 1889; Prüfer 1918 gave the bijection with length-(n−2) sequences over {1, …, n} that made the proof a one-liner. Core combinatorial identity connecting trees,…