1729: a remarkable number? ------------------------------
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The number N = 1,729 is the smallest natural number that can be written in two different ways as a sum of two cubes of natural numbers. Indeed:
1,729 = 123 + 13 = 103 + 93.
But is that enough to make it remarkable? Its fame may owe more to the anecdote involving Godfrey Hardy and Srinivasa Ramanujan (see opposite). 1,729 is sometimes called the Hardy–Ramanujan number.