A combinatorial derivation of the number of labeled forests

2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/69213Lajos Takacs gave a somewhat formidable alternating sum formula for the number of forests of unrooted trees on $n$ labeled vertices. Here we use a weight-reversing involution on suitable tree configurations to give a combinatorial derivation of Takacs' formula.3 pages, LaTeX, to appear Journal of Integer SequencesCombinatorics05C05A combinatorial derivation of the number of labeled foreststext