reserve a,b,c,d,m,x,n,j,k,l for Nat,
  t,u,v,z for Integer,
  f,F for FinSequence of NAT;
reserve p,q,r,s for real number;

theorem
  t divides (t+z)|^n implies t divides (t+z)|^n + z|^n
  proof
    assume
    A0: t divides (t+z)|^n;
    then t divides z|^n by Th11;
    hence thesis by WSIERP_1:4,A0;
  end;
