# 208

This number is a composite.

208 = 2^{2} + 3^{2} + 5^{2} + 7^{2} + 11^{2}. [Sladcik]

208^0 + 208^1 + 208^2 + 208^3 + ... + 208^35 + 208^36 is a prime number. [Raghava]

Smallest positive integer k>=2 such that no primes of the form (k+1)*k^n-1 with positive integer n are known. [Luen]

(There are 2 curios for this number that have not yet been approved by an editor.)

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