deletions | additions       diff --git a/Seti.tex b/Seti.tex  index 5d92480..fbfaf29 100644  --- a/Seti.tex  +++ b/Seti.tex 
...
In order to estimate the number of technological civilizations that might exist among the stars, in 1961 Frank Drake proposed the following simple equation   $N = R \times f_p \times n_e \times f_l \times f_i \times f_c \times L$