theorem Th14:
  a divides b implies (a|^c) divides (b|^c)
proof
  assume a divides b;
  then consider d be Nat such that
A1: a*d=b by NAT_D:def 3;
  b|^c =(a|^c)*(d|^c) by A1,NEWTON:7;
  hence thesis;
end;
