let x, y, z be set ; ( [<*x,y*>,and2c ] in InnerVertices (GFA1CarryStr x,y,z) & [<*y,z*>,and2a ] in InnerVertices (GFA1CarryStr x,y,z) & [<*z,x*>,and2 ] in InnerVertices (GFA1CarryStr x,y,z) & GFA1CarryOutput x,y,z in InnerVertices (GFA1CarryStr x,y,z) )
set f1 = and2c ;
set f2 = and2a ;
set f3 = and2 ;
set xy = [<*x,y*>,and2c ];
set yz = [<*y,z*>,and2a ];
set zx = [<*z,x*>,and2 ];
InnerVertices (GFA1CarryStr x,y,z) =
{[<*x,y*>,and2c ],[<*y,z*>,and2a ],[<*z,x*>,and2 ]} \/ {(GFA1CarryOutput x,y,z)}
by Th50
.=
{[<*x,y*>,and2c ],[<*y,z*>,and2a ],[<*z,x*>,and2 ],(GFA1CarryOutput x,y,z)}
by ENUMSET1:46
;
hence
( [<*x,y*>,and2c ] in InnerVertices (GFA1CarryStr x,y,z) & [<*y,z*>,and2a ] in InnerVertices (GFA1CarryStr x,y,z) & [<*z,x*>,and2 ] in InnerVertices (GFA1CarryStr x,y,z) & GFA1CarryOutput x,y,z in InnerVertices (GFA1CarryStr x,y,z) )
by ENUMSET1:def 2; verum