SemiBase

Variety V[8924]

The variety generated by [6, 8924]: all semigroups that satisfy every identity of [6, 8924]. 5 semigroups of order six generate it, and 3,683 semigroups of order six lie in it.

Shortest known basis

3 identities irredundant

  1. x² ≈ x⁴
  2. x²yx² ≈ yx²
  3. xyx ≈ xyx³

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[3006]V[8867]V[8920]V[8924]
Directly above
none: a maximal variety of the census
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[8924] in the inclusion graph, with everything above and below it.

Generated by 5 semigroups of order six

Contains 3,683 semigroups of order six

The semigroups of order six that satisfy the basis.

Show all 3,683