3 papers
math.NT2021
Connecting two types of representations of a permutation of $\F_q$
Zhiguo Ding
In this paper, we connect two types of representations of a permutation of the finite field $\F_q$. One type is algebraic, in which the permutation is represented as the compos…
cs.CR2021
Tangent-Chebyshev rational maps and Redei functions
Zhiguo Ding, Michael E. Zieve
Recently Lima and Campello de Souza introduced a new class of rational functions over odd-order finite fields, and explained their potential usefulness in cryptography. We show tha…
math.AG2021
The relative Riemann-Hurwitz formula
Zhiguo Ding, Michael E. Zieve
For any nonconstant f,g in C(x) such that the numerator H(x,y) of f(x)-g(y) is irreducible, we compute the genus of the normalization of the curve H(x,y)=0. We also prove an analog…