
theorem Th28:
  for p being 2_greater Prime,
      a,b being Integer
  st a gcd p = 1 & b gcd p = 1 & a,b are_congruent_mod p
  holds Leg(a,p) = Leg(b,p)
proof
let p be 2_greater Prime,
    a,b be Integer;
assume A1: a gcd p = 1 & b gcd p = 1 & a,b are_congruent_mod p;
thus Leg(a,p) = Lege(a,p) by Lm4 .= Lege(b,p) by Def1,A1,INT_5:29
             .= Leg(b,p) by Lm4;
end;
