 reserve o,o1,o2 for object;
 reserve n for Ordinal;
 reserve R,L for non degenerated comRing;
 reserve b for bag of 1;

theorem Th41:
   for f be sequence of R holds card (Support f) = card Support(f*BagN1)
   proof
     let f be sequence of R;
     card(Support f) = card(NBag1.:(Support f)) by Th40
     .= card(Support(f*BagN1)) by Th39;
     hence thesis;
   end;
