theorem
  for ins being Instruction of SCMPDS st InsCode ins = 1 holds ex a st
  ins = return a
proof
  let I be Instruction of SCMPDS such that
A1: InsCode I = 1;
  I in {[0,{},{}]} or I in S1 or I in S2 or I in S3 or I in S4 or I in S5
   by Lm1;
  then consider d1 such that
A2: I=[1,{},<*d1*>] by A1,Lm2,Lm4,Lm5,Lm6,Lm7;
  reconsider a=d1 as Int_position by AMI_2:def 16;
  take a;
  thus thesis by A2;
end;
