
theorem Lm1:
  for X be set,f be FinSequence of X,i be Nat st 1 <= i & i <= len f holds
    f.i=f/.i
 proof
  let X be set,f be FinSequence of X,i be Nat;
  assume 1 <= i & i <= len f; then
  i in dom f by FINSEQ_3:25;
  hence thesis by PARTFUN1:def 6;
 end;
