Schur rings over a Galois ring of odd characteristic

Schur rings over a product of Galois rings

The recently developed theory of Schur rings over a finite cyclic group is generalized to Schur rings over a ring R being a product of Galois rings of coprime characteristics. It is proved that if the characteristic of R is odd, then as in the cyclic group case any pure Schur ring over R is the tensor product of a pure cyclotomic ring and Schur rings of rank 2 over non-fields. Moreover, it is s...

Criterion of Maximal Period of a Trinomial over Nontrivial Galois Ring of odd Characteristic

In earlier eighties of XX century A.A.Nechaev has obtained the criterion of full period of a Galois polynomial over primary residue ring Z2n . Also he has obtained necessary conditions of maximal period of the Galois polynomial over Z2n in terms of coefficients of this polynomial. Further A.S.Kuzmin has obtained analogous results for the case of Galois polynomial over primary residue ring of od...

Enumeration of Schur Rings Over Small Groups

Commutative Schur rings over symmetric groups II :

We determine the commutative Schur rings over S6 that contain the sum of all the transpositions in S6. There are eight such types (up to conjugacy), of which four have the set of all the transpositions as a principal set of the Schur ring. 2010 MSC: 20C05, 20F55

Skew constacyclic codes over Galois rings

We generalize the construction of linear codes via skew polynomial rings by using Galois rings instead of finite fields as coefficients. The resulting non commutative rings are no longer left and right Euclidean. Codes that are principal ideals in quotient rings of skew polynomial rings by a two sided ideals are studied. As an application, skew constacyclic self-dual codes over GR(4) are constr...