reserve x for set;
reserve i,j for Integer;
reserve n,n1,n2,n3 for Nat;
reserve K,K1,K2,K3 for Field;
reserve SK1,SK2 for Subfield of K;
reserve ek,ek1,ek2 for Element of K;
reserve p for Prime;
reserve a,b,c for Element of GF(p);
reserve F for FinSequence of GF(p);

theorem Th14:
  i mod p is Element of GF(p)
  proof
    reconsider b = i mod p as Integer;
    b in NAT by INT_1:3,57;
    then reconsider b as Nat;
    b<p by INT_1:58;
    then b in Segm(p) by NAT_1:44;
    hence thesis;
  end;
