
theorem ThSTC0IS4:
  for x1,x2,x3,x4,x5,x6,x7 being non pair set holds
    InputVertices STC0IStr(x1,x2,x3,x4,x5,x6,x7) = {x1,x2,x3,x4,x5,x6,x7}
  proof
    let x1,x2,x3,x4,x5,x6,x7 be non pair set;
    set S1 = STC0IIStr(x1,x2,x3,x5,x6,x7);

    {x4} misses InnerVertices S1;
    then {x4} \ InnerVertices S1 = {x4} by XBOOLE_1:83;
    hence thesis by ZFMISC_1:59,ThSTC0IS3;
  end;
