SemiBase
← [6, 1258][6, 1260] →

[6, 1259] finitely based

self-dualother generated proof

[6, 1259] is a semigroup with 2 idempotents. It is finitely based: 6 identities define its variety, which 8 other semigroups of order six also generate.

Cayley table

·123456
1111151
2111152
3111153
4112151
5555515
6121456

The product of the row element and the column element, numbered as in Smallsemi. Blue: idempotents on the diagonal.

Structure

Smallsemi
SmallSemigroup(6, 1259)
Idempotents
1, 6
Zero
none
Identity
none
Nilpotent
no
Commutative
no
Regular
no
Group
no
𝒥-classes
5
Rank
4, generated by {3, 4, 5, 6}
Self-dual
yes: anti-isomorphic to itself

Identity basis

Shortest known basis: 6 identities irredundant

  1. x² ≈ x⁴
  2. xyx ≈ xyx³
  3. x²yzy ≈ x²zy²
  4. x²yzy ≈ xy²zx
  5. x²yzy ≈ yx²zy
  6. xyxzx ≈ xzxyx

Irredundant: none of these identities follows from the others; for each, a semigroup satisfies the others but not it. Obtained from a basis certified in Lean by removing identities that follow from the others, with the prover Vampire; the equivalence rests on Vampire's proofs, not on Lean. Shortest known, not known to be minimal.

Basis certified in Lean: 19 identities

  1. x² ≈ x⁴
  2. x³yx ≈ xyx
  3. x²yx ≈ xyx²
  4. x²yx² ≈ xyx
  5. x²y² ≈ xyxy
  6. x²y² ≈ xy²x
  7. x²y² ≈ yx²y
  8. xyx ≈ xyx³
  9. x³y² ≈ yx³y
  10. x²yzy ≈ x²zy²
  11. x²yzy ≈ xyxzy
  12. x²yzy ≈ xy²zx
  13. x²yzy ≈ xyzxy
  14. x²yzy ≈ xyzyx
  15. x²yzy ≈ xzxy²
  16. x²yzy ≈ xzyxy
  17. x²yzy ≈ xzy²x
  18. x²yzy ≈ yx²zy
  19. xyxzx ≈ xzxyx

Lean proof

Endpoint theorem: SemigroupBasis.Generated.Order6S5_107ParityKernel.S6_1259.representative_basis

BasisFor Generated.Order6S5_107ParityKernel.S6_1259.table.semigroup Generated.Order6S5_107ParityKernel.S6_1259.basis
Table
The theorem is about the semigroup with exactly this table.
Method
other generated proof. A machine-generated proof that builds on semigroups certified earlier: an adapter or wrapper of a transfer found by the campaign's search.
Size
Checking this class alone compiles 78 Lean files with 41,816 lines: the endpoint theorem and everything it imports, the shared library included. Of these, 135 lines are used by the proof of this class and of no other.
Census
SemiBase.Census.S6_1259 checks that the theorem is about the table of this class and concludes Classified; SemiBase.Catalogue.Order6.S6_1259 is the table, with the elements numbered 0 to 5.

Variety

[6, 1259] generates the variety V[1259]; 8 other semigroups of order six generate it too, and 3,131 semigroups of order six lie in it. [6, 1259] lies in 2 of the 505 varieties of the census, those whose basis it satisfies.

Directly above
Directly below

V[1259] in the inclusion graph, with the varieties above and below it.

Generating the same variety

Nearby tables

Semigroups whose Smallsemi table differs from this one in one or two entries (row, column), as the tables are listed, not up to renumbering.