SemiBase

Variety V[7943]

The variety generated by [6, 7943]: all semigroups that satisfy every identity of [6, 7943]. 9 semigroups of order six generate it, and 2,416 semigroups of order six lie in it.

Shortest known basis

5 identities irredundant

  1. x² ≈ x³
  2. xyx ≈ xyx²
  3. xyxzx ≈ xyzx
  4. xyxz² ≈ xyz²x
  5. xyxz² ≈ zxyxz

Irredundant: none of these identities follows from the others; for each, a semigroup satisfies the others but not it. Obtained from a certified basis by removing identities that follow from the others (Vampire). Shortest known, not known to be minimal.

Certified bases

Among the 505 varieties

V[3541]V[7950]V[3464]V[3471]V[7943]
Directly above
Directly below

A variety lies above another when it contains it. An inclusion holds when the basis of the smaller variety derives that of the larger one, proved by Vampire; it fails when a semigroup of order six lies in the one and not in the other.

Explore V[7943] in the inclusion graph, with everything above and below it.

Generated by 9 semigroups of order six

Contains 2,416 semigroups of order six

The semigroups of order six that satisfy the basis.

Show all 2,416