〈a, b | ab=aa, bba=ba〉

Properties

• Infinite non-commutative monoid

Completion parameters

• Reduction order: left-to-right ab

Complete rewriting system

1. ab ⇒ a²
2. b²a ⇒ ba
3. a⁴ ⇒ a³

Right Cayley graph (truncated)

Left Cayley graph (truncated)