On heterochromatic out-directed spanning trees in tournaments
arXiv:1601.04170 · doi:10.1007/s00373-015-1532-7
Abstract
Given a tournament T, let h(T) be the smallest integer k such that every arc-coloring of T with k or more colors produces at least one out-directed spanning tree of T with no pair of arcs with the same color. In this paper we give the exact value of h(T).