GraphingCalculator 3.5;
Window 48 171 760 811;
PaneDivider 221;
Slider 0 20;
SliderSteps 20;
SliderControlValue 1;
2D.BottomLeft -3.578125 -4.171875;
Expr y=atan([x]);
Color 2;
Expr y=sum([-1]^(k-1)*x^(2*k-1)/(2*k-1),k=1,n);