Sandbox

Math test

Warning: the Preview doesn't work for mathematical expressions. You have to Publish (or Save page).

$N=20*sqrt{D}$

$$\operatorname{erfc}(x) = \frac{2}{\sqrt{\pi}} \int_x^{\infty} e^{-t^2}\,dt = \frac{e^{-x^2}}{x\sqrt{\pi}}\sum_{n=0}^\infty (-1)^n \frac{(2n)!}{n!(2x)^{2n}}$$