reserve k for Nat;
reserve p for Prime;

theorem
  p*p <= k < 5041 implies
  p = 2 or p = 3 or p = 5 or p = 7 or p = 11 or p = 13 or p = 17 or 
  p = 19 or p = 23 or p = 29 or p = 31 or p = 37 or p = 41 or p = 43 or 
  p = 47 or p = 53 or p = 59 or p = 61 or p = 67
  proof
    assume p*p <= k < 5041;
    then p*p < 71*71 by XXREAL_0:2;
    hence thesis by Ttool71a,NAT_4:1;
  end;
