2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/114093In this note, first we refine Mandl's inequality. Then, we consider the product $p_1p_2... p_n$ and we refine some known lower bounds for it, and we find some upper bounds for it by using Mandl's inequality and its refinement and the AGM-Inequality.6 pages, no figureNumber TheoryClassical Analysis and ODEs11A41text