set f1 = and2b ;
set f2 = and2b ;
set f3 = and2b ;
set f4 = nor3 ;
let x, y, z be set ; :: thesis: ( x <> [<*y,z*>,and2b ] & y <> [<*z,x*>,and2b ] & z <> [<*x,y*>,and2b ] implies InputVertices (GFA3CarryStr x,y,z) = {x,y,z} )
set xy = [<*x,y*>,and2b ];
set yz = [<*y,z*>,and2b ];
set zx = [<*z,x*>,and2b ];
set xyz = [<*[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]*>,nor3 ];
set S = 1GateCircStr <*[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]*>,nor3 ;
set MI = GFA3CarryIStr x,y,z;
A1:
InnerVertices (1GateCircStr <*[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]*>,nor3 ) = {[<*[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]*>,nor3 ]}
by CIRCCOMB:49;
A2: InputVertices (1GateCircStr <*[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]*>,nor3 ) =
rng <*[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]*>
by CIRCCOMB:49
.=
{[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]}
by FINSEQ_2:148
;
assume A3:
( x <> [<*y,z*>,and2b ] & y <> [<*z,x*>,and2b ] & z <> [<*x,y*>,and2b ] )
; :: thesis: InputVertices (GFA3CarryStr x,y,z) = {x,y,z}
A4:
{x,y,z} \ {[<*[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]*>,nor3 ]} = {x,y,z}
by Lm2;
A5:
{[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]} \ {[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]} = {}
by XBOOLE_1:37;
thus InputVertices (GFA3CarryStr x,y,z) =
((InputVertices (GFA3CarryIStr x,y,z)) \ (InnerVertices (1GateCircStr <*[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]*>,nor3 ))) \/ ((InputVertices (1GateCircStr <*[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]*>,nor3 )) \ (InnerVertices (GFA3CarryIStr x,y,z)))
by CIRCCMB2:6, CIRCCOMB:55
.=
{x,y,z} \/ ({[<*x,y*>,and2b ],[<*y,z*>,and2b ],[<*z,x*>,and2b ]} \ (InnerVertices (GFA3CarryIStr x,y,z)))
by A1, A2, A3, A4, Th126
.=
{x,y,z} \/ {}
by A5, Th123
.=
{x,y,z}
; :: thesis: verum