Let A = F[x] hf(x)i , where f(x) is a monic polynomial over a finite field F. In this paper, we study the relation between A-codes and their duals. In particular, we state a counterexample and a correction to a theorem of Berger and El Amrani (Codes over finite quotients of polynomial rings, Finite Fields Appl. 25 (2014), 165–181) and present an efficient algorithm to find a system of generators for the dual of a given A-code. Also we characterize self-dual A-codes of length 2 and investigate when F-dual of A-codes is an A-code.
['Ashkan Nikseresht']
Dual of Codes over Finite Quotients of Polynomial Rings