theorem
  for f being FinSequence of TOP-REAL 2 st f is s.n.c. holds f is s.c.c.
proof
  let f be FinSequence of TOP-REAL 2;
  assume f is s.n.c.;
  then
  for i,j st i+1 < j & (i > 1 & j < len f or j+1 < len f) holds LSeg(f,i)
  misses LSeg(f,j) by TOPREAL1:def 7;
  hence thesis by GOBOARD5:def 4;
end;
