Crack the Inverse!
Geometry
Level
4
\[ \arctan\frac{1}{3}+\arctan\frac{1}{7}+\arctan\frac{1}{13}+ \ldots +\arctan\frac{1}{1+n+n^{2}}\\ +\arctan\frac{1}{n+1}=\ ? \]
by
Jessica Wang