Characterizing Rothe Diagrams

Rothe diagrams are diagrams which track inversions of a permutation. We define six main properties that Rothe diagrams fulfill: the southwest, dot, popping, numbering, step-out avoiding, and empty cell gap rules. We prove that – given an arbitrary bubble diagram – four different subsets of these properties provide sufficient criteria for the diagram to be a Rothe diagram. We also prove that when a set of ordered, freely floating, non-empty columns satisfy the numbering and step-out avoiding rules, then they can be arranged into a Rothe diagram.