1729 — The First Taxicab Number

Episode five of A Further Five Numbers, the BBC radio series presented by Simon Singh.

Curious properties sometimes lurk within seemingly undistinguished numbers. 1729 sparked one of maths most famous anecdotes: a young Indian, Srinivasa Ramanujan, lay dying of TB in a London hospital. G.H. Hardy, the leading mathematician in England, visited him there. "I came over in cab number 1729," Hardy told Ramanujan. "That seems a rather dull number to me."

"Oh, no!" Ramanujan exclaimed. "1729 is the smallest number you can write as the sum of two cubes, in two different ways." Most of us would use a computer to figure out that 1³ + 12³ = 9³ + 10³ = 1729. Ramanujan did it from his sickbed without blinking.

Also huffduffed as…

  1. 1729 — The First Taxicab Number

    —Huffduffed by boxman on September 11th, 2009

  2. 1729 — The First Taxicab Number

    —Huffduffed by eby on August 24th, 2009

  3. 1729 — The First Taxicab Number

    —Huffduffed by michele on August 20th, 2009

  4. 1729 — The First Taxicab Number

    —Huffduffed by chrispederick on October 1st, 2009

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    —Huffduffed by adactio one year ago

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    —Huffduffed by adactio one year ago