摘要
It is well known that the class group C（K） of an algebraic number field K is {1} iff the integer ring OK of K is UFD. In 1960, L. Carlitz discovered that K with C（K）= C2 can be characterized by C（K）（?）{1} and if a1…an=b1…bm for irreducible elements ai, bj∈OK then n=m. Recent-
