2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/102068In the paper, by the singular Riemann-Roch theorem, it is proved that the class of the e-th Frobenius power can be described using the class of the canonical module for a normal local ring of positive characteristic. As a corollary, we prove that the coefficient of the second term of the Hilbert-Kunz function of a finitely generated A-module M vanishes if A is a Q-Gorenstein ring and M is of finite projective dimension. For a normal algebraic variety X over a perfect field of positive characteristic, it is proved that the first Chern class of the direct image of the structure sheaf via e-th Frobenius power can be described using the canonical divisor of X.12 pages. to appear in J. AlgebraCommutative AlgebraAlgebraic Geometry13D40, 14C40The singular Riemann-Roch theorem and Hilbert-Kunz functionstext