Have you heard of Grahams number? (http://en.wikipedia.org/wiki/Graham%27s_number http://en.wikipedia.org/wiki/Graham%27s_number) It comes from a legitimate mat

Have you heard of Grahams number? (http://en.wikipedia.org/wiki/Graham%27s_number http://en.wikipedia.org/wiki/Graham%27s_number) It comes from a legitimate math proof, and it's unimaginably large. Or, I'm reminded of a proof, related to the Goldbach Conjecture, that every even number is the sum of at most 20 primes. There is a lot of precedent in math to find existence proofs for results that are completely useless for finding a practical solution.