> Because longer interstates may have many such supplemental routes, the numbers may repeat in each state along their route, but they will not repeat within a s

> Because longer interstates may have many such supplemental routes, the numbers may repeat in each state along their route, but they will not repeat within a state. https://en.wikipedia.org/wiki/List_of_auxiliary_Interstate_Highways https://en.wikipedia.org/wiki/List_of_auxiliary_Interstate_H...