The distinguishing index of the Cartesian product of countable graphs
The distinguishing index D′(G) of a graph G is the least cardinal d such that G has an edge colouring with d colours that is preserved only by the trivial automorphism.
We derive some bounds for this parameter for infinite graphs. In particular, we investigate the distinguishing index of the Cartesian product of countable graphs.
Finally, we prove that Dʹ(K2ℵ0) = 2, where K2ℵ0 is the infinite dimensional hypercube.
Issues from Vol 6, No 1 onward are partially supported by the Slovenian Research Agency from the Call for co-financing of scientific periodical publications