Popis: |
A permutation array(permutation code, PA) of length $n$ and distance $d$, denoted by $(n,d)$ PA, is a set of permutations $C$ from some fixed set of $n$ elements such that the Hamming distance between distinct members $\mathbf{x},\mathbf{y}\in C$ is at least $d$. In this correspondence, we present two constructions of PA from fractional polynomials over finite field, and a construction of $(n,d)$ PA from permutation group with degree $n$ and minimal degree $d$. All these new constructions produces some new lower bounds for PA. |