The role of Hilbert polynomials in commutative and homological algebra as well as in algebraic geometry and combinatorics is well known. A similar role in diffe

Difference algebra grew out of the study of algebraic difference equations with coefficients from functional fields. The first stage of this development of the

Algebra, as we know it today, consists of many different ideas, concepts and results. A reasonable estimate of the number of these different items would be some