SemiBase

Variety V[8861]

The variety generated by [6, 8861]: all semigroups that satisfy every identity of [6, 8861]. 8 semigroups of order six generate it, and 5,614 semigroups of order six lie in it.

Shortest known basis

4 identities irredundant

  1. x² ≈ x⁴
  2. xyx ≈ xyx³
  3. xyzy ≈ xzy²
  4. xyxz² ≈ xyz²x

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[8862]V[4061]V[4079]V[7404]V[8861]
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[8861] in the inclusion graph, with everything above and below it.

Generated by 8 semigroups of order six

Contains 5,614 semigroups of order six

The semigroups of order six that satisfy the basis.

Show all 5,614