7 papers
Sets of lengths in atomic unit-cancellative finitely presented monoids
Alfred Geroldinger, Emil Daniel Schwab
For an element of a monoid , its set of lengths is the set of all positive integers for which there is a factorization $a=u_1 \cdot \ld…
The Computation of the Möbius Function of a Möbius Category
Emil Daniel Schwab, Juan Villarreal
The paper presents some results for reducing the computation of the Möbius functon of a Möbius category that arises from a combinatorial inverse semigroup to that of locally finite…
A Partial Order on Bipartite Graphs with n Vertices
Emil Daniel Schwab
The paper examines a partial order on bipartite graphs (X1, X2, E) with n vertices, X1UX2={1,2,...,n}. This partial order is a natural partial order of subobjects of an object in a…
Image and Transfer Functions
Emil Schwab
We describe three transfer functors P, P', P" of an inverse exact category which arise from three transfer functions. We concentrate on some of the basic results which emerge from…
On the Combinatorial Inverse Monoid IO3
Emil Daniel Schwab, Romero Efren
In this paper we have compute the Mobius category and the Mobius function of the combinatorial inverse monoid IO3 of all order preserving partial bijections on the set M3={1,2,3}.…
On the Category of Partial Bijections
Emil Schwab
Categories of partial functions have become increasingly important principally because of their applications in theoretical computer science. In this note we prove that the categor…