Cube (algebra) however, easy to show that most numbers are not perfect cubes because "all" perfect cubes must have digital root 1, 8 or 9. That is their values modulo 9 may be only −1, 1 and 0. Moreover, the digital root of any number's cube can be determined by the remainder the number gives when divided by 3: Every positive integer can be written as the sum of nine (or fewer) positive cubes. This upper limit of nine cubes cannot be reduced because, for example, 23 cannot be written as the sum of fewer than nine positive cubes: The equation has
Ohio State Route 729 41 continues north to South Solon, and SR 729 turns right. North of Jeffersonville, the route makes three more 90-degree S-curves before entering Madison County. SR 729 ends at an intersection with SR 323 between the villages of South Solon and Midway. SR 729 was first designated in 1937 between what was then US 35 near Octa and Milledgevile (now the eastern terminus of SR 435) and its present northern terminus. In 1940, the route was extended south on a new alignment to Sabina and took over SR 350 from SR 73 to Sabina (SR 350 at that time ran