Rama, Ramanujan, and 1729

As is noted elsewhere on this site, I had a strong interest in mathematics prior to meeting Rama. I was always especially fascinated by the story of Ramanujan and the number 1729. Ramanujan was an Indian mathematician famous for developing some really esoteric and beautiful theorems in the early 20th century. He impressed the British mathematician G. Hardy with the depth of his abilities and was invited to England to collaborate with Hardy around 1913. Unfortunately, the change in climate, coupled with the restrictions of wartime rationing combined with Ramanujan's vegetarian diet did not do good things for Ramanujan's health, and he found himself in the hospital in 1917.

Ramanujan is well known, however, for an impromptu display of his mathematical abilities while in hospital. Hardy visited Ramanujan in the hospital, travelling in a taxi numbered 1729. When he arrived, Hardy commented to Ramanujan that 1729 was not a very interesting number. Ramanujan immediately replied that it is very interesting indeed: it is the smallest number which can be written in two different ways as the sum of two cubes:

1729 = 9*9*9 + 10*10*10 and 1729 = 1*1*1 + 12*12*12

Sadly, despite his abilities, Ramanujan never really fully regained his health, and he passed away shortly after his return to India in 1920.

So what does Ramanujan have to do with Rama (besides the similar names and the fact that they both had very successful lives which were cut short far too soon)? Well, I'd always been very fascinated with Ramanujan and with this story about the number 1729. In late 1992, I dropped my mentor, who was going away on a short vacation, off at the train station in San Jose, California. We chatted for a bit at the station, and then I returned to my car. I was very interested to notice a taxicab outside the station with a license plate which consisted of a few letters and then the numbers 1729. It was the first time I'd every seen a taxi with the numbers 1729, and given my fascination with Ramanujan I thought it was a powerful omen.

I soon discovered that this was very true. After I got home to my apartment on the Stanford campus, I got a short, excited call from my mentor. His train was about to leave, but he just wanted to inform me that I'd just been formally accepted as a student of Rama's.

It took awhile for it to really sink in what being a student of Rama meant, and it wasn't really until the next meeting with Rama where he talked with the group of new students he'd accepted about his decision that it began to solidify in my mind. However, the experience with the taxicab with licence number 1729, just before being accepted, has always stood out in my mind as being a strong omen of a connection between Rama, Ramanujan, and my own mathematical background.

Incidentally, more information about Ramanujan may be found in the book The Man Who Knew Infinity.