# 666

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$$2^2+3^2+5^2+7^2+11^2+13^2+17^2=666$$

If $(p_i)$ is the sequence of prime numbers, can we solve the equation:

$$\sum_{i=1}^k p_i^2 =\frac{n(n+1)}{2}$$

in $(k,n)$?

$p_1=2,p_7=17$, $(7,36)$ is solution.

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