2 problems

A rat-group is obtained by deleting the final relator from an Artin $n$-presentation of the trivial group, so it has a deficiency-one presentation. A knot group is characterized by…

González-Acuña's conjecture. If $A$ is an Artin $n$-presentation such that $|A|=1$, then $A\sim T$. This is one of the conjectures relating Artin presentations of the trivial group…