Number of Dudeney

A number of Dudeney is a whole which is a perfect Cube such as the sum of its figures gives the cubic Racine of this number. The name comes from Henry Dudeney, which noticed their existence in one of his enigmas, where a professor in retirement postulated to obtain a general method of extraction of the roots.

Here some of these numbers: 1 = 1 X 1 X 1; 1 = 1 512 = 8 X 8 X 8; 8 = 5 + 1 + 2 4913 = 17 X 17 X 17; 17 = 4 + 9 + 1 + 3 5832 = 18 X 18 X 18; 18 = 5 + 8 + 3 + 2 17576 = 26 X 26 X 26; 26 = 1 + 7 + 5 + 7 + 6 19683 = 27 X 27 X 27; 27 = 1 + 9 + 6 + 8 + 3

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