On constacyclic codes over ${\mathbb{Z}}_4[u]/⟨u^2-1⟩$ and their Gray images

Minjia Shi, Liqing Qian, Lin Sok +2

We first define a new Gray map from $R={\mathbb{Z}}_4+u{\mathbb{Z}}_4$ to ${\mathbb{Z}}_4^2$, where $u^2=1$ and study $(1+2u)$-constacyclic codes over $R$. Also of interest are some…