Counterexamples to Adám's conjecture on arc reversals in directed graphs
The author defines an infinite class of directed graphs with the property that reversing any arc increases the length of a longest directed cycle. From this he obtains counterexamples to Adám's conjecture that any directed graph with at least one directed cycle contains an arc whose reversal decreases the total number of directed cycles.
scientific article; zbMATH DE number 3985258
scientific article