When Srinivasa Ramanujan, the Indian mathematical genius and autodidact, was lying ill in England in the early 1900s, G.H. Hardy, the famous British mathematician, had gone to visit him. Of that meeting, Hardy was to write later: “I remember I had ridden in a taxicab number 1729 and remarked that the number seemed to me rather a dull one, and that I hoped it was not an unfavourable omen.”