Schwab, Emil Daniel Complete multiplicativity and complete additivity in Möbius categories. (English) Zbl 0955.05007 Ital. J. Pure Appl. Math. 3, 37-48 (1998). Summary: We prove characterizations of Lambek-Carlitz type for the completely multiplicative and the completely additive incidence functions in Möbius categories. In the case of a binomial-triangular category, we give a characterization of \(c\ell(x)\) as a completely additive incidence function (\(\ell(\alpha)\) is the length of the morphism \(\alpha\)). Finally we establish characterizations of Lambek-Carlitz type for \({\mathcal C}\)-binomial multiplicative and \({\mathcal C}\)-binomial additive formal power series via a full Möbius category of binomial type. MSC: 18B99 Special categories 06A07 Combinatorics of partially ordered sets 11A25 Arithmetic functions; related numbers; inversion formulas Keywords:complete multiplicativity; complete additivity; incidence functions; Möbius categories; Lambek-Carlitz type PDF BibTeX XML Cite \textit{E. D. Schwab}, Ital. J. Pure Appl. Math. 3, 37--48 (1998; Zbl 0955.05007)