2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/124170We summarise our results for the random $ε$--1-in-3 satisfiability problem, where $ε$ is a probability of negation of the variable. We employ both rigorous and heuristic methods to describe the SAT/UNSAT and Hard/Easy transitions.2 pages, introductory level, proceed. for the Les Houches Session LXXXV 2006 on Complex SystemsStatistical MechanicsDisordered Systems and Neural NetworksComputational Complexitytext