ON THE DUAL CODES OF SKEW CONSTACYCLIC CODES

Let F-q be a finite field with q elements and denote by theta : F-q -> F-q an automorphism of F-q. In this paper, we deal with skew constacyclic codes, that is, linear codes of F-q(n) which are invariant under the action of a semi-linear map phi(alpha,theta) : F-q(n) -> F-q(n) defined by phi(alpha,theta) (a(0),..., a(n-2), a(n-1)) := (alpha theta(a(n-1)), theta(a(0)), ...,theta(a(n-2))) for some alpha is an element of F-q \ {0} and n >= 2. In particular, we study some algebraic and geometric properties of their dual codes and we give some consequences and research results on 1-generator skew quasi-twisted codes and on MDS skew constacyclic codes.