A Square matrix
is called reducible if the indices 1, 2, ...,
can be divided into two disjoint nonempty sets , , ..., and , , ..., (with
) such that

for , 2, ..., and , 2, ..., . A Square Matrix which is not reducible is said to be Irreducible.

**References**

Gradshteyn, I. S. and Ryzhik, I. M. *Tables of Integrals, Series, and Products, 5th ed.* San Diego, CA:
Academic Press, p. 1103, 1979.

© 1996-9

1999-05-25