SemiBase

Variety V[3613]

The variety generated by [6, 3613]: all semigroups that satisfy every identity of [6, 3613]. 1 semigroup of order six generates it, and 1,920 semigroups of order six lie in it.

Shortest known basis

4 identities irredundant

  1. x² ≈ x³
  2. xyx ≈ xyx²
  3. x²y² ≈ yx²y
  4. xyzt ≈ xzyt

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[3942]V[7644]V[7689]V[7974]V[8029]V[1029]V[3338]V[3346]V[3613]
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[3613] in the inclusion graph, with everything above and below it.

Generated by 1 semigroup of order six

Contains 1,920 semigroups of order six

The semigroups of order six that satisfy the basis.

Show all 1,920