
theorem
  2141 is prime
proof
  now
    2141 = 2*1070 + 1; hence not 2 divides 2141 by NAT_4:9;
    2141 = 3*713 + 2; hence not 3 divides 2141 by NAT_4:9;
    2141 = 5*428 + 1; hence not 5 divides 2141 by NAT_4:9;
    2141 = 7*305 + 6; hence not 7 divides 2141 by NAT_4:9;
    2141 = 11*194 + 7; hence not 11 divides 2141 by NAT_4:9;
    2141 = 13*164 + 9; hence not 13 divides 2141 by NAT_4:9;
    2141 = 17*125 + 16; hence not 17 divides 2141 by NAT_4:9;
    2141 = 19*112 + 13; hence not 19 divides 2141 by NAT_4:9;
    2141 = 23*93 + 2; hence not 23 divides 2141 by NAT_4:9;
    2141 = 29*73 + 24; hence not 29 divides 2141 by NAT_4:9;
    2141 = 31*69 + 2; hence not 31 divides 2141 by NAT_4:9;
    2141 = 37*57 + 32; hence not 37 divides 2141 by NAT_4:9;
    2141 = 41*52 + 9; hence not 41 divides 2141 by NAT_4:9;
    2141 = 43*49 + 34; hence not 43 divides 2141 by NAT_4:9;
  end;
  then for n being Element of NAT st 1 < n & n*n <= 2141 & n is prime
  holds not n divides 2141 by XPRIMET1:28;
  hence thesis by NAT_4:14;
end;
