Combinatorial matrix theory is a rich branch of mathematics that combines combinatorics, graph theory, and linear
algebra. It includes the theory of matrices with prescribed combinatorial properties,
including permanents and Latin
squares. It also comprises combinatorial proof of classical algebraic theorems
such as Cayley-Hamilton theorem.

As mentioned in Season 4 episodes 407 "Primacy" and 412 "Power"
of the television crime drama NUMB3RS, professor Amita Ramanujan's primary teaching
interest is combinatorial matrix theory.