SemiBase

A certified basis of 23 identities

This list of identities is a basis, proved in Lean, of 59 semigroups of order six, all of which generate the variety V[4022]. Removing the identities that follow from the others leaves 3 identities (Vampire); the variety page shows the shortest known basis.

Identifier sb-be4758ea2bdf05e9 in the data of the bases-min seal.

Certified for

The identities

  1. x² ≈ x⁴
  2. x³y ≈ xy
  3. x²yx ≈ xyx²
  4. x²yx ≈ xy³
  5. x²yx² ≈ xyx
  6. x²yxy ≈ xy²
  7. x²y² ≈ xyxy
  8. x²y² ≈ xy²x
  9. x²y²x ≈ xy²
  10. x²y³ ≈ xyx
  11. xyx ≈ xyx³
  12. xyx ≈ xyxy²
  13. xyx ≈ xy²xy
  14. xyx²y ≈ xy²
  15. xyxyx ≈ xy²
  16. xy² ≈ xy²x²
  17. x²yxz ≈ xyz
  18. x²yz ≈ xyxz
  19. xyx²z ≈ xyz
  20. xyzx ≈ xzyx
  21. xyzy ≈ xzy²
  22. x²yzx ≈ xy²zy
  23. x²yzy ≈ xy²zx