Invariant decomposition of functions with respect to commuting invertible transformations

Bálint Farkas, Viktor Harangi, Tamás Keleti +1

Consider a_1,a_2,...,a_n, arbitrary elements of R. We characterize those real functions f that decompose into the sum of a_j-periodic functions, i.e., f=f_1+...+f_n with D_{a_j}f(x…