Problem 2491. Dudeney Numbers: Numbers which are the cube of their decimal sum

Created by Peter Cook

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Last Solution submitted on Sep 14, 2021

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Alex Drikitis on 14 Sep 2021 at 11:34

is there any negative dudeney number?

Dyuman Joshi on 14 Sep 2021 at 16:36

Depends upon how you define them.

If you are taking - sign outside the cube of the sum, every negative number corresponding to the positive Dudeney number is a Dudeney number.

If you define by the way OP has defined, -1 qualifies as a Dudeney number.

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Solution 484340

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Jean-Marie Sainthillier on 9 Aug 2014

Great minds think alike.

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Problem 2491. Dudeney Numbers: Numbers which are the cube of their decimal sum

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Problem 2491. Dudeney Numbers: Numbers which are the cube of their decimal sum

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