You have a keen eye for subtle references! I didn't expect many people to get that one :) There's another math anecdote reference hidden in there as well - probably even more obscure than Karl's sum.

Upon reading this comment had to skim the whole thing looking for more (hadn't yet finished reading). No more maths references than tau found yet. :/

Ramanujan and Hardy are two well-known mathematicians who collaborated in Britain between 1914 and 1920. One day Hardy took taxi number 1729 to visit Ramanujan, and remarked to him that he (Hardy) could think of nothing special about the number (1729). Ramanujan replied that it was in fact the first number expressible as the sum of two cubes in two different ways (1^3 + 12^3 = 9^3 + 10^3). The story has since become an anecdotal symbol of Ramanujan's brilliant mind.

http://en.wikipedia.org/wiki/1729_(number)

That's a very obscure reference, though, so I apologize for sending anyone looking based on my previous comment.

Haha I'd heard this anecdote before, so it's my own fault for missing it. :)

Thanks for the great article and indeed fun references!

Just as well I searched for 'Gauss' before commenting. :)

(so, yes. :P)

Ha! I got karl, was wondering who fred was.