On the Harborth constant of $C_3\oplus C_{3n}$

Philippe Guillot, Luz Elimar Marchan, Oscar Ordaz +2

For a finite abelian group $(G,+,0)$ the Harborth constant $\mathsf{g}(G)$ is the smallest integer $k$ such that each squarefree sequence over $G$ of length $k$, equivalently each…