2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/70778We show that every knot type admits a pair of diagrams that cannot be made identical without using Reidemeister Omega_2-moves. We also show that our proof is compatible with known results for the other move types, in the sense that every knot type admits a pair of diagrams that cannot be made identical without using all of the move types.8 pages, 8 figures. Changed title and added mention of a partial result by Vassily ManturovGeometric Topology57M25text