Copolymer chains are characterized by chain length, chain composition, and sequence length distributions. Despite the wealth of information these distributions provide, they are incapable of determining the microstructure and concentration of individual chain types along the conversion path at the level of "polymeric isomers", which are chains of same length and composition but have different monomeric sequences. This work is intended to develop the mathematical equations of "digital encoding of polymer chains", which is a technique that encapsulates all the information about polymer chain architecture in a unique descriptive manner and is capable of determining the concentrations of all polymer chain types and their isomers. Two types of histograms can be generated: the encoded sequence length distribution (SLD) and the chain type distribution (CTD), which enable a specific visualization of results.