# Summation Thug Life!

Algebra Level 3

$\large 1^2 - 2^2 + 3^2 - 4^2 + 5^2 - \cdots + (4n-1)^2 - (4n)^2$

If the sum above can be expressed in the form of $an^2 + bn + c$, where $a,b$ and $c$ are integer constants, find $a+b+c$.

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