=====Distributive residuated lattices===== Abbreviation: **DRL** ====Definition==== A \emph{distributive residuated lattice} is a residuated lattice $\mathbf{L}=\langle L, \vee, \wedge, \cdot, e, \backslash, /\rangle$ such that $\vee, \wedge$ are distributive: $x\wedge(y\vee z) =(x\wedge y) \vee (x\wedge z)$ Remark: ==Morphisms== Let $\mathbf{L}$ and $\mathbf{M}$ be distributive residuated lattices. A morphism from $\mathbf{L}$ to $\mathbf{M}$ is a function $h:L\rightarrow M$ that is a homomorphism: $h(x\vee y)=h(x)\vee h(y)$, $h(x\wedge y)=h(x)\wedge h(y)$, $h(x\cdot y)=h(x)\cdot h(y)$, $h(x\backslash y)=h(x)\backslash h(y)$, $h(x/y)=h(x)/h(y)$, $h(e)=e$ ====Examples==== Example 1: ====Basic results==== ====Properties==== ^[[Classtype]] |variety | ^[[Equational theory]] | | ^[[Quasiequational theory]] |undecidable | ^[[First-order theory]] |undecidable | ^[[Locally finite]] |no | ^[[Residual size]] |unbounded | ^[[Congruence distributive]] |yes | ^[[Congruence modular]] |yes | ^[[Congruence n-permutable]] |yes, n=2 | ^[[Congruence regular]] |no | ^[[Congruence e-regular]] |yes | ^[[Congruence uniform]] |no | ^[[Congruence extension property]] |no | ^[[Definable principal congruences]] |no | ^[[Equationally def. pr. cong.]] |no | ^[[Amalgamation property]] | | ^[[Strong amalgamation property]] | | ^[[Epimorphisms are surjective]] | | ====Finite members==== $\begin{array}{lr} f(1)= &1\\ f(2)= &1\\ f(3)= &3\\ f(4)= &20\\ f(5)= &115\\ f(6)= &899\\ f(7)= &7782\\ f(8)= &80468\\ \end{array}$ ====Subclasses==== [[Commutative distributive residuated lattices]] [[Distributive FLe-algebras]] ====Superclasses==== [[Distributive multiplicative lattices]] [[Residuated lattices]] ====References==== [(Ln19xx> )]