[Home]Distributive lattices

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Difference (from revision 3 to current revision) (author diff)

Changed: 92c92

yes, $\langle c,d\rangle\in Cg(a,b)\iff (a\wedge b)\wedge c=(a\wedge b)\wedge d \mbox{and} (a\vee b)\vee c=(a\vee b)\vee d

yes, (c,d) ∈ Cg(a,b)  ⇔   (ab)∧c = (ab)∧d  and  (ab)∨c = (ab)∨d

Abbreviation: DLat

Definition

A distributive lattice is a lattice L = (L,∨,∧) such that
distributes over :   x∧( yz)  = ( xy) ∨( xz) .

Definition

A distributive lattice is a lattice L = (L,∨,∧) such that
distributes over :   x∨( yz)  = ( xy) ∧( xz) .

Definition

A distributive lattice is a lattice L = (L,∨,∧) such that
( xy) ∨( xz) ∨( yz)  = ( xy) ∧( xz) ∧( yz) .

Definition

A distributive lattice is a lattice L = (L,∨,∧) such that L has no sublattice isomorphic to the diamond M3 or the pentagon N5

Morphisms

Let L and M be distributive lattices. A morphism from L to M is a function h : LM that is a homomorphism: h(xy) = h(x)∨h(y)  and  h(xy) = h(x)∧h(y).

Some results

Examples

(P(S),∪,∩, ⊆ ), the collection of subsets of a sets S, ordered by inclusion.

Properties

Classtype variety
Equational theory decidable
Quasiequational theory decidable
First-order theory undecidable
Congruence distributive yes
Congruence modular yes
Congruence n-permutable no
Congruence regular no
Congruence uniform no
Congruence extension property yes
Definable principal congruences no
Equationally definable principal congruences yes, (c,d) ∈ Cg(a,b)  ⇔   (ab)∧c = (ab)∧d  and  (ab)∨c = (ab)∨d
Amalgamation property yes
Strong amalgamation property no
Epimorphisms are surjective no
Locally finite yes
Residual size 2

Finite members

[Size 1]?:  1
[Size 2]?:  1
[Size 3]?:  1
[Size 4]?:  2
[Size 5]?:  3
[Size 6]?:  5
[Size 7]?:  8
[Size 8]?:  15
[Size 9]?:  26
[Size 10]?:  47
[Size 11]?:  82
[Size 12]?:  151
[Size 13]?:  269
[Size 14]?:  494
[Size 15]?:  891
[Size 16]?:  1639
[Size 17]?:  2978
[Size 18]?:  5483
[Size 19]?:  10006
[Size 20]?:  18428
Values known up to size 49 [Erne, Heitzig, Reinhold (2002)]

Subclasses

[One-element algebras]?
Bounded distributive lattices
[Complete distributive lattices]?

Superclasses

Modular lattices
Semidistributive lattices


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Last edited July 29, 2003 9:15 pm (diff)
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