title: Simple way to replace nth element in a vector in clojure?
body: <p>E.g., I have a vector <code>[1, 2, 3]</code>, and I want to update the second element so that the vector becomes <code>[1, 5, 3]</code>.  In other languages, I would just do something like <code>array[1] = 5</code>, but I'm not aware of anything that would allow me to do this easily in Clojure.</p>
  
  <p>Thoughts on how to accomplish this, or on whether I should be using a different data structure?</p>