
theorem :: WEDDWITT
  for R being finite Skew-Field holds card MultGroup R = card R - 1
proof
  let R be finite Skew-Field;
  set G = MultGroup R;
  the carrier of G = NonZero R by Def1;
  then card the carrier of G = card R - card {0.R} by CARD_2:44;
  hence thesis by CARD_1:30;
end;
