Definition:Taxicab Number/Historical Note

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Historical Note on Taxicab Number

The first person to find an integer with this property was Bernard Frénicle de Bessy in $1657$.

He discovered $5$ instances of these numbers in response to a challenge by Leonhard Paul Euler:

\(\ds 1729\) \(=\) \(\, \ds 10^3 + 9^3 \, \) \(\, \ds = \, \) \(\ds 12^3 + 1^3\)
\(\ds 4104\) \(=\) \(\, \ds 15^3 + 9^3 \, \) \(\, \ds = \, \) \(\ds 16^3 + 2^3\)
\(\ds 39 \, 312\) \(=\) \(\, \ds 15^3 + 33^3 \, \) \(\, \ds = \, \) \(\ds 34^3 + 2^3\)
\(\ds 40 \, 033\) \(=\) \(\, \ds 16^3 + 33^3 \, \) \(\, \ds = \, \) \(\ds 34^3 + 9^3\)
\(\ds 20 \, 683\) \(=\) \(\, \ds 24^3 + 19^3 \, \) \(\, \ds = \, \) \(\ds 27^3 + 10^3\)


The name taxicab number arises from an anecdote related by G.H. Hardy about a visit to Srinivasa Ramanujan in hospital in a taxicab whose number was $1729$.


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