  The attributes of Euler's constant Gamma have been a baffling problem to the
world's mathematicians in the number theory field. In 1900, when German
mathematician D. Hilbert addressed the 2nd International Congress of
Mathematicians, he suggested twenty-three previously unsolved problems to the
international mathematical field. The 7th of these problems pertained to
Euler's constant Gamma. After investigating this problem for many years, the
author has proved that Euler's constant Gamma is an irrational number.
