Functions with variative-coordinate polynomiality over group
A class of VCP-functions, that is, of functions with the variative-coordinate polynomiality over group, is defined. It is an extension of the class of VCP-functions over primary ring of residues. An algorithm for finding coordinates for group elements is presented. It is shown that the class of VCP-functions over UTn(Zp) does not coincide with the class of polynomial function. A formula for constructing the inverse of a bijective VCP-function over UTn(Zp) is proposed.