Pancyclicity and bipancyclicity are classical properties in graph theory, ensuring the existence of cycles of all admissible lengths in general and bipartite graphs. These notions were strengthened by vertex-(bi)pancyclicity, which requires cycles of every length to contain a prescribed vertex. However, prior work has focused almost exclusively on single-vertex constraints, leaving the multi-vertex setting largely unexplored. Motivated by this gap, we introduce and study k-vertex-constrained (bi)pancyclicity, which demands cycles of all admissible lengths to pass through an arbitrary set of k specified vertices. This paper presents Qn is 3-vertex-constrained bipancyclic if n ≥ 5.
Zhang et al. (Mon,) studied this question.