deletions | additions       diff --git a/Investigation.tex b/Investigation.tex  index 6c594c7..35a6d85 100644  --- a/Investigation.tex  +++ b/Investigation.tex 
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(0;n|d);m=(0;n)|(d;m), \;\; d\in[0,9]  \end{equation}  For the pipe and semi-comma operations we have identity \begin{equation}  0|a = a \\