deletions | additions       diff --git a/layout.md b/layout.md  index 435ea2e..963c3e1 100644  --- a/layout.md  +++ b/layout.md 
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section_Relations_Let_A_and__.tex  section_Functions_In_the_set__.tex  section_Sets_with_Operations_Groups__.tex  section_Number_Sets_the_Properties__.tex section_Modular_Arithmetic_subsection_Introduction__.tex