fix markup issues

Author: mmcky

lectures/markov_chains_I.md

@@ -107,8 +107,6 @@ From  US unemployment data, Hamilton {cite}`Hamilton2005` estimated the followin
 
 ```
 
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 Here there are three **states**
 
 * "ng" represents normal growth
@@ -836,8 +834,6 @@ ax.scatter(ψ_star[0], ψ_star[1], ψ_star[2], c='k', s=60)
 plt.show()
 ```
 
-+++ {"user_expressions": [], "tags": []}
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 Here
 
 * $P$ is the stochastic matrix for recession and growth {ref}`considered above <mc_eg2>`.
@@ -1082,8 +1078,6 @@ Solution 1:
 
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 Since the matrix is everywhere positive, there is a unique stationary distribution.
 
 Solution 2: