SemiBase

Variety V[7982]

The variety generated by [6, 7982]: all semigroups that satisfy every identity of [6, 7982]. 1 semigroup of order six generates it, and 1,499 semigroups of order six lie in it.

Shortest known basis

6 identities irredundant

  1. x² ≈ x³
  2. xyx ≈ xy²x
  3. xyx ≈ xyxyx
  4. x²y²x² ≈ y²x²y²x²
  5. xyxzx ≈ xzxyx
  6. x²y²x²y²z² ≈ x²y²x²z²

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[7430]V[7434]V[7976]V[7982]
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[7982] in the inclusion graph, with everything above and below it.

Generated by 1 semigroup of order six

Contains 1,499 semigroups of order six

The semigroups of order six that satisfy the basis.

Show all 1,499