deletions | additions       diff --git a/Equation.tex b/Equation.tex  index b12bc53..1639df0 100644  --- a/Equation.tex  +++ b/Equation.tex 
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$N = R \times f_p \times n_e \times f_l \times f_i \times f_c \times L$  where \begin{itemize}   \item  $N$ is the number of civilizations in the Milky Way Galaxy with whom we could make contact. \item  $R$ is the rate of star formation, formation (star/year),  which tells how many stars are born every year in our Galaxy. \item  $n_e$ is the average number of habitable planets in any planetary system \end{itemize}  All the  $f$ termn terms  are factors $\le 1$, corresponding to \begin{itemize}  \item $f_p$ is the fraction of stars that have planets   \item $f_l$ is the fraction of planets where life actually begins