Zero Divisors Among Digraphs

  title={Zero Divisors Among Digraphs},
  author={Richard Hammack and Heather Smith},
  journal={Graphs and Combinatorics},
A digraph C is called a zero divisor if there exist non-isomorphic digraphs A and B for which A ×C ∼= B ×C , where the operation is the direct product. In other words, C being a zero divisor means that cancellation property A×C ∼= B×C ⇒ A ∼= B fails. Lovász proved that C is a zero divisor if and only if it admits a homomorphism into a disjoint union of… CONTINUE READING