deletions | additions       diff --git a/friends.tex b/friends.tex  index b520f89..2e56eca 100644  --- a/friends.tex  +++ b/friends.tex 
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Another particular fact about these fields, is that exist elements whose powers cover all the non-zero elements of thield itself. As an example consider the elements $3$ and $5$ in $\ZZ_7$.  The powers of $3$ are  \begin{align}  & 3 \\&  3^2\equiv 9\equiv 2\\&  3^3\equiv 3^2\cdot 3\equiv 2\cdot 3\equiv 6 \\&  3^4\equiv 3^3\cdot 3\equiv 6\cdot 3\equiv 4 \\&  3^5\equiv 3^4\cdot 3\equiv 4\cdot 3\equiv 5 \\&  3^6\equiv 3^5\cdot 3\equiv 5\cdot 3\equiv 1 \end{align}  The powers of $5$ are  \begin{align}