An algorithm with a delay of $\mathcal{O}(kΔ)$ for enumerating connected induced subgraphs of size $k$

The problem of enumerating connected subgraphs of a given size in a graph has been extensively studied in recent years. In this short communication, we propose an algorithm with a delay of $\mathcal{O}(k\Delta)$ for enumerating all connected induced subgraphs of size $k$ in an undirected graph $G=(V, E)$, where $k$ and $\Delta$ are respectively the size of subgraphs and the maximum degree of $G$. The proposed algorithm improves upon the current best delay bound $\mathcal{O}(k^2\Delta)$ for the connected induced subgraph enumeration problem in the literature.