
theorem Th16:
  for L being non empty ZeroStr, p being AlgSequence of L st len p
  = 1 holds p = <%p.0%> & p.0 <> 0.L
proof
  let L be non empty ZeroStr, p being AlgSequence of L such that
A1: len p = 1;
  thus p=<%p.0%> by A1,ALGSEQ_1:def 5;
  hence thesis by A1,ALGSEQ_1:14;
end;
