set f1 = and2 ;
set f2 = and2 ;
set f3 = and2 ;
set f0 = xor2 ;
let x, y, z be set ; ( z <> [<*x,y*>,xor2 ] & x <> [<*y,z*>,and2 ] & y <> [<*z,x*>,and2 ] & z <> [<*x,y*>,and2 ] implies ( x in InputVertices (BitGFA0Str x,y,z) & y in InputVertices (BitGFA0Str x,y,z) & z in InputVertices (BitGFA0Str x,y,z) ) )
assume A1:
( z <> [<*x,y*>,xor2 ] & x <> [<*y,z*>,and2 ] & y <> [<*z,x*>,and2 ] & z <> [<*x,y*>,and2 ] )
; ( x in InputVertices (BitGFA0Str x,y,z) & y in InputVertices (BitGFA0Str x,y,z) & z in InputVertices (BitGFA0Str x,y,z) )
set S = BitGFA0Str x,y,z;
InputVertices (BitGFA0Str x,y,z) = {x,y,z}
by A1, Th41;
hence
( x in InputVertices (BitGFA0Str x,y,z) & y in InputVertices (BitGFA0Str x,y,z) & z in InputVertices (BitGFA0Str x,y,z) )
by ENUMSET1:def 1; verum