〈a, b | aaa=a, babbab=a〉

Properties

• Infinite commutative monoid
• Isomorphic to commutative presentation: 〈a, b | 3b=b, 4a+b=2b〉
• Grothendieck group is ℤ₈

Completion parameters

• Reduction order: left-to-right ab

Complete rewriting system

1. ba ⇒ ab
2. a³ ⇒ a
3. ab⁴ ⇒ a²

Right Cayley graph (truncated)