Categories of Semigroups with Divisor Theory
Characterization of power digraphs modulo
A power digraph modulo , denoted by , is a directed graph with as the set of vertices and as the edge set, where and are any positive integers. In this paper we find necessary and sufficient conditions on and such that the digraph has at least one isolated fixed point. We also establish necessary and sufficient conditions on and such that the digraph contains exactly two components. The primality of Fermat number is also discussed.
Cipolla pseudoprimes.
Combinatorial properties of products of graphs
Compact integers and factorials
Correction to the paper: On the sum-of-Divisors Function of the numbers of Fermat and Ferentinou-Nicolacopoulou
Cribrum algebraicum oder die cofunctionale Entstehung der Primzahlen.