2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/229835The duality is a fundamental property of the finite multiple harmonic sums (MHS). In this paper, we prove a duality result for certain generalizations of MHS which appear naturally as the differences of MHS. We also prove a formula for the differences of these generalized MHS.12 pages; minor corrections; to appear in Journal of Number TheoryNumber Theorytext