
theorem
  883 is prime
proof
  now
    883 = 2*441 + 1; hence not 2 divides 883 by NAT_4:9;
    883 = 3*294 + 1; hence not 3 divides 883 by NAT_4:9;
    883 = 5*176 + 3; hence not 5 divides 883 by NAT_4:9;
    883 = 7*126 + 1; hence not 7 divides 883 by NAT_4:9;
    883 = 11*80 + 3; hence not 11 divides 883 by NAT_4:9;
    883 = 13*67 + 12; hence not 13 divides 883 by NAT_4:9;
    883 = 17*51 + 16; hence not 17 divides 883 by NAT_4:9;
    883 = 19*46 + 9; hence not 19 divides 883 by NAT_4:9;
    883 = 23*38 + 9; hence not 23 divides 883 by NAT_4:9;
    883 = 29*30 + 13; hence not 29 divides 883 by NAT_4:9;
  end;
  then for n being Element of NAT st 1 < n & n*n <= 883 & n is prime
  holds not n divides 883 by XPRIMET1:20;
  hence thesis by NAT_4:14;
