  Floquet theory, first published in 1883 for periodic linear differential
equations, is extended in this paper to multitime diagonal recurrences. We find
explicitly a monodromy matrix, and we comment its eigenvalues (called Floquet
multipliers). The Floquet point of view brings about an important
simplification: the initial linear diagonal recurrence system is reduced to a
linear recurrence system, with constant coefficients along "diagonal lines".
The results are applied to the discrete multitime Samuelson-Hicks models, with
constant, respectively multi-periodic, coefficients, in order to find bivariate
sequences with economic meaning. For constant coefficients case, it was found
also the generating function; for multi-periodic coefficients case, we
determined the Floquet multipliers.
