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
USS Georgia (SSGN-729) USS Georgia (SSGN-729) USS "Georgia" (SSBN-729/SSGN-729), an , is the second ship of the United States Navy to be named for the fourth state. The contract to build her was awarded to the Electric Boat Division of General Dynamics Corporation in Groton, Connecticut on 20 February 1976 and her keel was laid down on 7 April 1979. She was launched on 6 November 1982 sponsored by Mrs. Sheila M. Watkins, and commissioned as a fleet ballistic missile submarine (SSBN) on 11 February 1984, with Captain A. W. Kuester commanding the Blue crew and Captain M. P. Gray commanding the Gold