This puzzle involved telnetting into some computer that was set up during the Hunt. We don't know what sort of puzzle was involved there. But since it was set up on port 1729, and 1729 is the Hardy-Ramanujan number, the smallest number expressible as the sum of two positive cubes in two different ways (12^{3}+1^{3} = 10^{3}+9^{3}), it may well have been math related.