deletions | additions       diff --git a/9090+3.tex b/9090+3.tex  index 7aec203..acbefe9 100644  --- a/9090+3.tex  +++ b/9090+3.tex 
...
\section{Analysing the 169 digit prime}  We may chop into a $11\times11$ $13\times13$  grid \\ \\ 1 1 5 0 7 4 7 9 8 6 1 9 1 \\  0 2 4 1 6 5 7 0 7 7 1 0 0 \\  1 1 5 0 7 4 7 9 8 6 1 9 1 \\ 
...
0 2 4 1 6 5 7 0 7 7 1 0 0 \\  1 1 5 0 7 4 7 9 8 6 1 9 1 \\  \\  We can now see $11$ $13$  vertical period $2$ substrings. \\ 10...,12...,54...,01...,76...,77...,90...,87...,67...,11...,90...,10...