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We describe odd-length-cube tilings of the n-dimensional q-ary torus what includes q-periodic integer lattice tilings of R^n. In the language of coding theory these tilings correspond to perfect codes with respect to the maximum metric. A complete characterization of the two-dimensional tillings is presented and in the linear case, a description of general matrices, isometry and isomorphism classes is provided. Several methods to construct perfect codes from codes of smaller dimension or via sections are derived. We introduce a special type of matrices (perfect matrices) which are in correspondence with generator matrices for linear perfect codes in arbitrary dimensions. For maximal perfect codes, a parametrization obtained allows to describe isomorphism classes of such codes. We also approach the problem of what isomorphism classes of abelian groups can be represented by q-ary n-dimensional perfect codes of a given cardinality N.
We investigate perfect codes in $mathbb{Z}^n$ under the $ell_p$ metric. Upper bounds for the packing radius $r$ of a linear perfect code, in terms of the metric parameter $p$ and the dimension $n$ are derived. For $p = 2$ and $n = 2, 3$, we determine
Perfect truncated-metric codes (PTMCs) in the $n$-dimensio-nal grid $Lambda_n$ of $mathbb{Z}^n$ ($0<ninmathbb{Z}$) and its quotient toroidal grids were obtained via the truncated distance $rho(u,v)$ in $mathbb{Z}^n$ given between vertices $u=(u_1,cdo
Let $d, n in mathbb{Z}^+$ such that $1leq d leq n$. A $d$-code $mathcal{C} subset mathbb{F}_q^{n times n}$ is a subset of order $n$ square matrices with the property that for all pairs of distinct elements in $mathcal{C}$, the rank of their differenc
Let $G$ be a simple graph with $2n$ vertices and a perfect matching. The forcing number $f(G,M)$ of a perfect matching $M$ of $G$ is the smallest cardinality of a subset of $M$ that is contained in no other perfect matching of $G$. Among all perfect
We define the rank-metric zeta function of a code as a generating function of its normalized $q$-binomial moments. We show that, as in the Hamming case, the zeta function gives a generating function for the weight enumerators of rank-metric codes. We