% Mizar problem: t30_enumset1,enumset1,538,5 
fof(t30_enumset1, conjecture,  (! [A] :  (! [B] : k1_enumset1(A, A, B)=k2_tarski(A, B)) ) ).
fof(commutativity_k2_tarski, axiom,  (! [A, B] : k2_tarski(A, B)=k2_tarski(B, A)) ).
fof(commutativity_k2_xboole_0, axiom,  (! [A, B] : k2_xboole_0(A, B)=k2_xboole_0(B, A)) ).
fof(dt_k1_enumset1, axiom, $true).
fof(dt_k1_tarski, axiom, $true).
fof(dt_k2_tarski, axiom, $true).
fof(dt_k2_xboole_0, axiom, $true).
fof(idempotence_k2_xboole_0, axiom,  (! [A, B] : k2_xboole_0(A, A)=A) ).
fof(t1_enumset1, axiom,  (! [A] :  (! [B] : k2_tarski(A, B)=k2_xboole_0(k1_tarski(A), k1_tarski(B))) ) ).
fof(t29_enumset1, axiom,  (! [A] : k2_tarski(A, A)=k1_tarski(A)) ).
fof(t3_enumset1, axiom,  (! [A] :  (! [B] :  (! [C] : k1_enumset1(A, B, C)=k2_xboole_0(k2_tarski(A, B), k1_tarski(C))) ) ) ).
