set f1 = and2 ;
set f2 = and2 ;
set f3 = and2 ;
let x, y, z be set ; ( x <> [<*y,z*>,and2 ] & y <> [<*z,x*>,and2 ] & z <> [<*x,y*>,and2 ] implies ( x in InputVertices (GFA0CarryStr x,y,z) & y in InputVertices (GFA0CarryStr x,y,z) & z in InputVertices (GFA0CarryStr x,y,z) ) )
assume
( x <> [<*y,z*>,and2 ] & y <> [<*z,x*>,and2 ] & z <> [<*x,y*>,and2 ] )
; ( x in InputVertices (GFA0CarryStr x,y,z) & y in InputVertices (GFA0CarryStr x,y,z) & z in InputVertices (GFA0CarryStr x,y,z) )
then
InputVertices (GFA0CarryStr x,y,z) = {x,y,z}
by Th17;
hence
( x in InputVertices (GFA0CarryStr x,y,z) & y in InputVertices (GFA0CarryStr x,y,z) & z in InputVertices (GFA0CarryStr x,y,z) )
by ENUMSET1:def 1; verum