reserve i,j,k,l,m,n for Nat,
  D for non empty set,
  f for FinSequence of D;
reserve X for compact Subset of TOP-REAL 2;
reserve r for Real;
reserve f for non trivial FinSequence of TOP-REAL 2;
reserve f for non constant standard special_circular_sequence;

theorem Th49:
  1 <= i & i <= j & j < m & m <= n & n <= len f & (1 < i or n <
  len f) implies L~mid(f,j,i) misses L~mid(f,n,m)
proof
  mid(f,i,j) = Rev mid(f,j,i) by FINSEQ_6:196;
  then L~mid(f,i,j) = L~mid(f,j,i) by SPPOL_2:22;
  hence thesis by Th48;
end;
