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 Th14:
  l>0 & t divides z implies t divides z|^l
  proof
    assume
    A0: l>0 & t divides z;
    then consider n be Nat such that
    A1: l = 1+n by NAT_1:10,14;
    z|^(1+n) = z|^1*z|^n by NEWTON:8
    .= z*z|^n;
    hence thesis by A0,A1,INT_2:2;
  end;
