〈a, b | aab=ab, abba=aa〉

Properties

• Infinite non-commutative monoid

Completion parameters

• Reduction order: left-to-right ab

Complete rewriting system

1. a³ ⇒ a²
2. a²b ⇒ ab
3. ab²a ⇒ a²

Right Cayley graph (truncated)

Left Cayley graph (truncated)