
theorem
  for x,b being non pair set holds x in InputVertices IncrementStr(x,b)
  & b in InputVertices IncrementStr(x,b)
proof
  let x,b be non pair set;
  InputVertices IncrementStr(x,b) = {x,b} by FACIRC_1:40;
  hence thesis by TARSKI:def 2;
end;
