2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/136792Lehmer's question is equivalent to one about generalized growth rates of Lefschetz numbers of iterated pseudo-Anosov surface homeomorphisms. One need consider only homeomorphisms that arise as monodromies of fibered knots in lens spaces L(n,1), n>0. Lehmer's question for Perron polynomials is equivalent to one about generalized growth rates of words under injective free group endomorphisms.Small corrections; to appear in Math. Proc. Cambridge Phil. Soc. 17 pages, 1 figureGeometric TopologyDynamical Systems57M25; 37C25; 11R06Lehmer's question, knots and surface dynamicstext