On curves of odd gonality

摘要

1. Introduction. Two basic theorems for the study of special divisors on curves are Clifford's theorem and H. Martens' dimension theorem. Recall that by the Riemann-Roch theorem it is sufficient to investigate effective divisors D of degree deg D < g on a curve C of genus g. Clifford's theorem then states that for an effective divisor D of degree degZ)