A “Calculus of Sequences” had started by the 1936 publication of Ward suggesting the possible range for extensions of operator calculus of Rota-Mullin, considered by several authors and after Ward. Because of convenience we shall call the Wards calculus of sequences in its afterwards elaborated form – a ψ-calculus. The notation used by Ward, Viskov, Markowsky and Roman is accommodated in confor...