reserve m for Nat;
reserve P for Instruction-Sequence of SCM+FSA;

theorem
  for a,b being Int-Location, f being FinSeq-Location holds a <> b
  implies b :=len f does not destroy a
proof
  let a,b be Int-Location;
  let f be FinSeq-Location;
  assume
A1: a <> b;
  now
    let c be Int-Location;
    let g be FinSeq-Location;
A2: InsCode (b :=len f) = 11 by SCMFSA_2:28;
    hence a := c <> b :=len f by SCMFSA_2:18;
    thus AddTo(a,c) <> b :=len f by A2,SCMFSA_2:19;
    thus SubFrom(a,c) <> b :=len f by A2,SCMFSA_2:20;
    thus MultBy(a,c) <> b :=len f by A2,SCMFSA_2:21;
    thus Divide(a,c) <> b :=len f & Divide(c,a) <> b :=len f by A2,SCMFSA_2:22;
    thus a :=(g,c) <> b :=len f by A2,SCMFSA_2:26;
    thus a :=len g <> b :=len f by A1,SF_MASTR:11;
  end;
  hence thesis;
end;
