reserve X for set;
reserve a,b,c,k,m,n for Nat;
reserve i,j for Integer;
reserve r,s for Real;
reserve p,p1,p2,p3 for Prime;

theorem
  1 + 3 + 3|^2 + 3|^3 + 3|^4 = 11|^2 by Lm8,Lm9,Lm10,Lm11;
