EntityQ1937896· pop 9· linked from 8 articlesRoad coloring problemSign in to savetheorem that every aperiodic strongly-connected out-regular directed graph can be labeled to give a synchronizable deterministic finite automatonConnectionsdirected graphEntityprime numberEntitydigital object identifierEntitytheoremEntitygraph theoryEntityperiodic functionEntityQ118398Entityfour color theoremEntityconjectureEntitymazeEntityfinite-state machineEntitynodeEntitygraph coloringEntitynecessity and sufficiencyEntitydegreeEntitycycleEntitystrongly connected componentEntityRoy AdlerEntityBenjamin WeissEntitymultiple edgesEntityCategoriesAutomata (computation)CombinatoricsGraph coloringMathematics and cultureTheorems in graph theoryTopological graph theory