=====Generalized Boolean algebras===== Abbreviation: **GBA** ====Definition==== A \emph{generalized Boolean algebra} is a [[Brouwerian algebras]] $\mathbf{A}=\langle A, \vee, \wedge, 1, \rightarrow\rangle$ such that $x\vee y=(x\rightarrow y)\rightarrow y$ ==Morphisms== Let $\mathbf{A}$ and $\mathbf{B}$ be generalized Boolean algebras. A morphism from $\mathbf{A}$ to $\mathbf{B}$ is a function $h:A\rightarrow B$ that is a homomorphism: $h(x\vee y)=h(x)\vee h(y)$, $h(x\wedge y)=h(x)\wedge h(y)\ \mbox{and} h(1)=1$, $h(x\rightarrow y)=h(x)\rightarrow h(y)$ ====Examples==== Example 1: ====Basic results==== ====Properties==== ^[[Classtype]] |variety | ^[[Equational theory]] |decidable | ^[[Quasiequational theory]] |decidable | ^[[First-order theory]] |decidable | ^[[Locally finite]] |yes | ^[[Residual size]] |$2$ | ^[[Congruence distributive]] |yes | ^[[Congruence modular]] |yes | ^[[Congruence n-permutable]] |yes, $n=2$ | ^[[Congruence regular]] |yes | ^[[Congruence e-regular]] |yes, $e=1$ | ^[[Congruence uniform]] |yes | ^[[Congruence extension property]] |yes | ^[[Definable principal congruences]] |yes | ^[[Equationally def. pr. cong.]] |yes | ^[[Amalgamation property]] |yes | ^[[Strong amalgamation property]] |yes | ^[[Epimorphisms are surjective]] |yes | ====Finite members==== $\begin{array}{lr} f(1)= &1\\ f(2)= &1\\ f(3)= &0\\ f(4)= &1\\ f(5)= &0\\ f(6)= &0\\ \end{array}$ ====Subclasses==== [[Boolean algebras]] ====Superclasses==== [[Brouwerian algebras]] [[Wajsberg hoops]] ====References==== [(Ln19xx> )]