31 lines
1.2 KiB
Text
31 lines
1.2 KiB
Text
A [[wp:Hardy–Ramanujan number|taxicab number]] (the definition that is being used here) is a positive integer that can be expressed as the sum of two positive cubes in more than one way.
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The first taxicab number is '''1729''', which is:
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::: 1<sup>3</sup> + 12<sup>3</sup> and also
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::: 9<sup>3</sup> + 10<sup>3</sup>.
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Taxicab numbers are also known as:
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::* taxi numbers
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::* taxi-cab numbers
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::* taxi cab numbers
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::* Hardy-Ramanujan numbers
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;Task:
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* Compute and display the lowest 25 taxicab numbers (in numeric order, and in a human-readable format).
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* For each of the taxicab numbers, show the number as well as it's constituent cubes.
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;Extra credit
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* Show the 2,000<sup>th</sup> taxicab number, and a half dozen more
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;See also:
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* [[oeis:A001235|A001235: taxicab numbers]] on The On-Line Encyclopedia of Integer Sequences.
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* [http://mathworld.wolfram.com/Hardy-RamanujanNumber.html Hardy-Ramanujan Number] on MathWorld.
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* [http://mathworld.wolfram.com/TaxicabNumber.html taxicab number] on MathWorld.
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* [[wp:Taxicab_number|taxicab number]] on Wikipedia (includes the story on how taxi-cab numbers came to be called).
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<br><br>
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