IEEE Transactions on Information Theory, cilt.69, sa.9, ss.5597-5603, 2023 (SCI-Expanded)
The Galois ring GR(4Δ) is the residue ring Z4[x]/(h(x)), where h(x) is a basic primitive polynomial of degree Δ over Z4. For any odd Δ larger than 1, we construct a partition of GR(4Δ)\{0} into 6-subsets of type {a, b,b -ab-b,b-a,b-b, a+b} and 3-subsets of type {c,b-c, 2c} such that the partition is invariant under the multiplication by a nonzero element of the Teichmuller set in GR(4Δ) and, if Δ is not a multiple of 3, under the action of the automorphism group of GR(4Δ). As a corollary, this implies the existence of quasi-cyclic additive 1-perfect codes of index (2Δ b- 1) in D((2Δb-1)(2Δb-2)/6, 2Δb-1) where D(m, n) is the Doob metric scheme on Z2m+n.