Let F-2m be a finite field of cardinality 2(m), R = F-2m[u]/ = F-2m + uF(2m) +u(2)F(2m) + u(3)F(2m) (u(4) = 0) which is a finite chain ring, and n is an odd positive integer. For any delta, alpha is an element of F-2m...
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Let F-2m be a finite field of cardinality 2(m), R = F-2m[u]/< u(4)> = F-2m + uF(2m) +u(2)F(2m) + u(3)F(2m) (u(4) = 0) which is a finite chain ring, and n is an odd positive integer. For any delta, alpha is an element of F-2m(x) an explicit representation for the dual code of any (delta + alpha u(2))-constacyclic code over R of length 2n is given. And some dual codes of (1 + u(2))-constacyclic codes over R of length 14 are constructed. For the case of delta = 1, all distinct self-dual (1 + alpha u(2))-constacyclic codes over R of length 2n are determined. (C) 2019 Elsevier B.V. All rights reserved.
For a simple-root lambda-constacyclic code Cover F-q, let and be the subgroups of the automorphism group of C generated by the cyclic shift rho, and by the cyclic shift rho and the scalar multiplication group rho, r...
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For a simple-root lambda-constacyclic code Cover F-q, let and be the subgroups of the automorphism group of C generated by the cyclic shift rho, and by the cyclic shift rho and the scalar multiplication group rho, respectively. Let N-G(C*) be the number of orbits of a subgroup Gof the automorphism group of C acting on C* = C\constacyclic code. In this paper, we establish explicit formulas for N- (C*) and N- (C*). Consequently, we derive a upper bound on the number of non-zero weights of C. We present some irreducible and reducible lambda-constacyclic codes, which show that the upper bound is tight. A sufficient condition to guarantee N- (C*) = N- (C*) is presented. (c) 2023 Elsevier Inc. All rights reserved.
Let F-pm be a finite field of cardinality p(m) and R-3= F-pm[u]/, where p is a prime, mis a positive integer and u(3)= 0. Laaouine et al. (2021) [7] obtained the torsion code and the number of codewords of cyclic code...
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Let F-pm be a finite field of cardinality p(m) and R-3= F-pm[u]/< u(3)>, where p is a prime, mis a positive integer and u(3)= 0. Laaouine et al. (2021) [7] obtained the torsion code and the number of codewords of cyclic codes of length p(s) over F(p)m[u]/< u(3)>, but some of the results were wrong, which in this paper, we improve them. By a new method, we compute the number of codewords of these codes. Finally, by using a one-to-one correspondence between cyclic and alpha-constacyclic codes of length psover F-pm[u]/< u(3)>, we generalize these results to alpha-constacyclic codes, where a is a non-zero element of the finite field F(p)m. (c) 2024 Published by Elsevier B.V.
In recent years, there have been intensive activities in the area of constructing quantum maximum distance separable(MDS for short) codes from constacyclic MDS codes through the Hermitian construction. In this paper, ...
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In recent years, there have been intensive activities in the area of constructing quantum maximum distance separable(MDS for short) codes from constacyclic MDS codes through the Hermitian construction. In this paper, a new class of quantum MDS code is constructed, which extends the result of [Theorems 3.14–3.15, Kai, X., Zhu, S., and Li,P., IEEE Trans. on Inf. Theory, 60(4), 2014, 2080–2086], in the sense that our quantum MDS code has bigger minimum distance.
For different odd primes k , l , p , and positive integers s , m , n , the polynomial x k s l m p n - lambda in F q [x] is explicitly factorized, where p is the characteristic of F q , lambda is an element of F q &...
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For different odd primes k , l , p , and positive integers s , m , n , the polynomial x k s l m p n - lambda in F q [x] is explicitly factorized, where p is the characteristic of F q , lambda is an element of F q & lowast;. All repeated-root constacyclic codes and their dual codes of length k s l m p n over F q are characterized. In addition, the characterization and enumeration of all linear complementary dual (LCD) cyclic and negacyclic codes of length k s l m p n over F q are obtained. (c) 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Let a and b be two non-zero elements of a finite field F-q, where q>2. It has been shown that if a and b have the same multiplicative order in F-q, then the families of a-constacyclic and b-constacyclic codes over ...
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Let a and b be two non-zero elements of a finite field F-q, where q>2. It has been shown that if a and b have the same multiplicative order in F-q, then the families of a-constacyclic and b-constacyclic codes over F-q are monomially equivalent. In this paper, we investigate the monomial equivalence of a-constacyclic and b-constacyclic codes when a and b have distinct multiplicative orders. We present novel conditions for establishing monomial equivalence in such constacyclic codes, surpassing previous methods of determining monomially equivalent constacyclic and cyclic codes. As an application, we use these results to search for new linear codes more systematically. In particular, we present more than 70 new record-breaking linear codes over various finite fields, as well as new binary quantum codes.
Matrix product codes are generalizations of some well-known classes of codes, including generalized Reed-Muller codes and repeated-root constacyclic codes. Recently, a bound for the minimum symbol-pair distance of a m...
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Matrix product codes are generalizations of some well-known classes of codes, including generalized Reed-Muller codes and repeated-root constacyclic codes. Recently, a bound for the minimum symbol-pair distance of a matrix product code was given by (Luo et al., 2023), leading to the creation of new families of MDS symbol-pair codes. In this paper, we provide lower and upper bounds for the minimum b-symbol distance of matrix product codes, which naturally extends some of the results by (Luo et al., 2023). Examples meeting the bounds are included to illustrate our results. As an initial application of these new bounds, we establish that constacyclic codes (repeated-root or otherwise) meeting specific criteria can indeed be classified as matrix product codes, and present bounds on the minimum b-symbol distance of such constacyclic codes. Additionally, we determine all the minimum b-symbol distances of Reed-Muller codes as a secondary application of the new bounds.
In this article, we deal with additive codes over the Frobenius ring R2R3 := Z(2)[u]/ x Z(2)[u]/. First, we study constacyclic codes over R-2 and R-3 and find their generator polynomials. With the help of these genera...
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In this article, we deal with additive codes over the Frobenius ring R2R3 := Z(2)[u]/< u(2)> x Z(2)[u]/< u(3)>. First, we study constacyclic codes over R-2 and R-3 and find their generator polynomials. With the help of these generator polynomials, we determine the structure of constacyclic codes over R2R3. We use Gray maps to show that constacyclic codes over R2R3 are essentially binary generalized quasi-cyclic codes. Moreover, we obtain a number of binary codes with good parameters from these R2R3-constacyclic codes. Besides, several weight enumerators are computed, and the corresponding MacWilliams identities are established.
An equivalence relation called isometry is introduced to classify constacyclic codes over a finite field: the polynomial generators of constacyclic codes of length l(t)p(s) are characterized, where p is the characteri...
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An equivalence relation called isometry is introduced to classify constacyclic codes over a finite field: the polynomial generators of constacyclic codes of length l(t)p(s) are characterized, where p is the characteristic of the finite field and l is a prime different from p. (C) 2012 Elsevier Inc. All rights reserved.
Abstract constacyclic codes are an important class of linear codes in coding theory. Many optimal linear codes are directly derived from constacyclic codes. In this paper, a new Gray map between codes over Fp + uFp ...
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Abstract constacyclic codes are an important class of linear codes in coding theory. Many optimal linear codes are directly derived from constacyclic codes. In this paper, a new Gray map between codes over Fp + uFp + u^2Fp and codes over Fp is defined, where p is an odd prime. By means of this map, it is shown that the Gray image of a linear (1 + u + u2)-constacyclic code over Fp + uFp + u^2Fp of length n is a repeated-root cyclic code over Fp of length pn. Furthermore, some examples of optimal linear cyclic codes over F3 from (1 + u + u2)-constacyclic codes over F3 + uF3 + u^2F3 are given.
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