Henry Ernest Dudeney/Puzzles and Curious Problems/122 - A Question of Cubes/Solution

by : $122$

 * A Question of Cubes

Solution

 * $\ds \sum_{n \mathop = 14}^{25} n^3 = 14^3 + 15^3 + 16^3 + \cdots + 25^3 = 97 \, 344 = 312^2$