2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/124498We introduce essential subtrees for terms (trees) and tree automata . There are some results concerning independent sets of subtrees and separable sets for a tree and an automaton.9 pages, 2 figures, Sixth International Conference on Discrete Mathematics and Applications, Bansko, 2001Computational ComplexityDiscrete MathematicsF.1.1; F.1.2text