2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/156902We define an analogue of signed Eulerian numbers $f_{n,k}$ for involutions of the symmetric group and derive some combinatorial properties of this sequence. In particular, we exhibit both an explicit formula and a recurrence for $f_{n,k}$ arising from the properties of its generating function.10 pagesCombinatorics05A05; 05A15; 05A19; 05E10text