deletions | additions       diff --git a/layout.md b/layout.md  index 83a1b85..00c1f97 100644  --- a/layout.md  +++ b/layout.md 
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Basic_Verlet_formulation_is_as__.tex  vec_v_t_vec_v__.tex  Now_we_need_to_show__.tex  vec_x_t_Delta_t__1.tex