deletions | additions       diff --git a/Intro.tex b/Intro.tex  index 79ccd4a..b0aee56 100644  --- a/Intro.tex  +++ b/Intro.tex 
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And so on:  \[ \rho(t) = \rho(0) + \sum_{n=0}^{\infty}{\left(\frac{-i}{\hbar}\right)^n \sum_{n=1}^{\infty}{\left(\frac{-i}{\hbar}\right)^n  \int_{0}^{t}{dt_1 \int_{0}^{t_1}{dt_2 ... \int_{0}^{t_{n-1}}{dt_n [H(t_1),[H(t_2),...[H(t_n),\rho(t_n)]...]]}}}}\]