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 2020-06-14, 08:04 #1 enzocreti   Mar 2018 10000101002 Posts 512 Is 512 the only cube with the property that if the digits are reversed, the reverse 215 is a cube minus one?
2020-06-14, 09:13   #2
paulunderwood

Sep 2002
Database er0rr

107516 Posts

Quote:
 Originally Posted by enzocreti Is 512 the only cube with the property that if the digits are reversed, the reverse 215 is a cube minus one?
0^3 is a cube. Reversed is 0 and that is 1 less than 1 which is also a cube: 1^3

2020-06-14, 11:44   #3
paulunderwood

Sep 2002
Database er0rr

11·383 Posts

Quote:
 Originally Posted by enzocreti Is 512 the only cube with the property that if the digits are reversed, the reverse 215 is a cube minus one?
If you allow for leading zeroes to removed there are infinite many solutions:

(8*10^n)^3 == 512*10^(3*n). Reversed it is 000...000215 which is 1 fewer than 6^3

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