### Constructing R-sequencings and terraces for groups of even order

#### Abstract

The problem of finding R-sequencings for abelian groups of even orders has been reduced to that of finding R\(^*\)-sequencings for abelian groups of odd orders except in the case when the Sylow 2-subgroup is a non-cyclic non-elementary-abelian group of order~8. We partially address this exception, including all instances when the group has order \(8t\) for \(t\) congruent to 1, 2, 3 or 4 \((\mod{7})\). As much is known about which odd-order abelian groups are R\(^*\)-sequenceable, we have constructions of R-sequencings for many new families of abelian groups. The construction is generalisable in several directions, leading to a wide array of new R-sequenceable and terraceable non-abelian groups of even order.

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