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- - 512 (https://www.mersenneforum.org/showthread.php?t=25625)

enzocreti

2020-06-14 08:04

512

Is 512 the only cube with the property that if the digits are reversed, the reverse 215 is a cube minus one?

paulunderwood

2020-06-14 09:13

[QUOTE=enzocreti;547933]Is 512 the only cube with the property that if the digits are reversed, the reverse 215 is a cube minus one?[/QUOTE]

0^3 is a cube. Reversed is 0 and that is 1 less than 1 which is also a cube: 1^3

paulunderwood

2020-06-14 11:44

[QUOTE=enzocreti;547933]Is 512 the only cube with the property that if the digits are reversed, the reverse 215 is a cube minus one?[/QUOTE]

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 :smile:

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