let f be set ; for x, y being non pair object holds InputVertices (1GateCircStr (<*x,y*>,f)) is without_pairs
let x, y be non pair object ; InputVertices (1GateCircStr (<*x,y*>,f)) is without_pairs
set p = <*x,y*>;
let z be pair object ; FACIRC_1:def 2 not z in InputVertices (1GateCircStr (<*x,y*>,f))
assume A1:
z in InputVertices (1GateCircStr (<*x,y*>,f))
; contradiction
InputVertices (1GateCircStr (<*x,y*>,f)) = {x,y}
by Th40;
hence
contradiction
by A1, TARSKI:def 2; verum