reserve S for with_non_trivial_Instructions COM-Struct;
reserve i,j,k for No-StopCode Instruction of S,
        I,J,K for MacroInstruction of S;
reserve i1,i2,i3,i4,i5,i6 for No-StopCode Instruction of S;
reserve I,J for non empty NAT-defined finite Function;
reserve I,J for MacroInstruction of S;

theorem Th51:
  (i1 ';' i2 ';' i3 ';' i4).2 = IncAddr(i3,2)
 proof
  LastLoc(i1 ';' i2 ';' i3) = 3 by Th31;
  hence (i1 ';' i2 ';' i3 ';' i4).2 = (i1 ';' i2 ';' i3).2 by Th23,Th28
        .= IncAddr(i3,2) by Th50;
 end;
