SemiBase

Variety V[5480]

The variety generated by [6, 5480]: all semigroups that satisfy every identity of [6, 5480]. 1 semigroup of order six generates it, and 3,374 semigroups of order six lie in it.

Shortest known basis

3 identities irredundant

  1. x²y ≈ y²x
  2. xyz ≈ xzy
  3. xy²zt ≈ xyzt

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[5689]V[871]V[2611]V[2800]V[5480]
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[5480] in the inclusion graph, with everything above and below it.

Generated by 1 semigroup of order six

Contains 3,374 semigroups of order six

The semigroups of order six that satisfy the basis.

Show all 3,374