0

2207

A Lucas number, L15 specifically. Lucas numbers are generated like fibonacci numbers but with a starting set of 1,3 instead of 1,1. L15 is the largest Lucas number that is (a) prime and (b) has a composite index. How anybody can prove that, I don't know, but it's a pretty astonishing fact.

0

2221

2221 = 1^2 + 1^3 + 2^5 + 3^7
That is, the sum of the first four fibonacci numbers raised to the power of the first four primes.

0

2341

One of several primes built out of the first four integers. Oddly enough, you can't construct ANY primes from the first 2 integers, nor the first 3, nor the first 5 nor the first 6. Savor the moment.

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