〈a, b | abba=abb, bbbb=1〉

Properties

• Infinite non-commutative monoid

Completion parameters

• Reduction order: left-to-right ab

Complete rewriting system

1. a² ⇒ a
2. ab²a ⇒ ab²
3. b⁴ ⇒ 1

Right Cayley graph (truncated)

Left Cayley graph (truncated)