theorem
  seq is bounded_below & seq1 is divergent_to-infty implies seq-seq1 is
  divergent_to+infty
proof
  assume that
A1: seq is bounded_below and
A2: seq1 is divergent_to-infty;
  (-jj)(#)seq1 is divergent_to+infty by A2,Th14;
  hence thesis by A1,Th9;
end;
