〈a, b | abba=ab, bbbb=b〉

Properties

• Infinite non-commutative monoid

Completion parameters

• Reduction order: left-to-right b/a

Complete rewriting system

1. b⁴ ⇒ b
2. aba ⇒ ab³
3. ab²a ⇒ ab
4. ab³a ⇒ ab²

Right Cayley graph (truncated)

Left Cayley graph (truncated)