Algebraic curves over F-3 with many rational points

Abstract

We present a method to find curves over the finite field F-3 with many rational points. The method is based in an arithmetic study of linear systems of projective plane curves of a given degree and prescribed singularities. We have found curves of genera 4, 5, 6, 7 and 8 which in the cases of genera 5 and 8 improve the existent bounds for the number of rational points, and in the cases of genera 4, 6 and 7 reach these bounds.