2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/116675The present notes contain the material of the lectures given by the author at the summer school on ``Modular Forms and their Applications'' at the Sophus Lie Conference Center in the summer of 2004.72 pagesNumber TheoryAlgebraic Geometry11F41, 11F55, 11F27, 11G15text