2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/221974The paper deals with sigma-games on grid graphs (in dimension 2 and more) and conditions under which any completely symmetric configuration of lit vertices can be reached -- in particular the completely lit configuration -- when starting with the all-unlit configuration. The answer is complete in dimension 2. In dimension greater than or equal to 3, the answer is complete for the sigma^+ -game, and for the sigma^- -game if at least one of the sizes is even. The case sigma^-, dimension greater than or equal to 3 and all sizes odd remains open.The bibliography has been correctedCombinatoricsRings and Algebras05B30, 37B15text