# One more Ramanujan Sum

Number Theory Level 5

Let $$c_{2015}(n)$$ be the sum of the $$n^\text{th}$$ powers of all the primitive $$2015^\text{th}$$ roots of unity, $$\omega.$$ Find the minimal value of $$c_{2015}(n)$$ for all positive integers $$n$$.

This year's problem

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