2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/78258Any two triangulations of a closed surface with the same number of vertices can be transformed into each other by a sequence of regular flips, provided the number of vertices exceeds a number N depending on the surface. Examples show that in general N is bigger than the minimal number of vertices of a triangulation. The existence of N was known, but no estimate. This paper provides an estimate for N that is linear in the Euler characteristic of the surface.4 pages, 5 figures. Final versionGeometric TopologyCombinatorics57Q15 (Primary) 57Q25, 57M15 (Secondary)text