On a class of constacyclic codes over the ring Z4[u]/< u² − 3 >

Abstract

In this paper, λ-constacyclic codes and skew-λ-constacyclic codes over the ring R = Z4[u]/< u² − 3 > are studied for λ = 3 and 2 + 3u. Introducing new Gray maps from R to the copies of Z4, we observed that Gray images of λ-constacyclic codes over R are cyclic, quasi-cyclic and permutation equivalent to quasi-cyclic codes over Z4. λconstacyclic codes of odd length over R and generating polynomial of the Gray images are studied. Further, it is observed that the images of skew-λ- constacyclic codes over R are cyclic, quasi-cyclic and permutation equivalent to quasi-cyclic codes over Z4.