title: Copy a cell unless it contains the same value as a previous cell
body: <p>On one worksheet I have 4 cells (e.g., A1 through A4) that can each contain one of a handful of text options (e.g., red, blue, green, or yellow). So on one worksheet these four cells may be filled in as: A1=Red, A2=Green, A3=Red, A4=Red.</p>
  
  <p>On a second worksheet, I want to fill in a single cell with the types of color chosen for those four cells. In the given example, this cell on the second worksheet would read "Red/Green."</p>
  
  <p>I'm looking for a formula I can put into the cell on the second sheet that will check the four cells and pull only one of each that contains a unique text. Is there a formula that would, for example, copy A1, then copy A2 only if it is different from A1, then copy A3 only if it is different from both A1 and A2, then copy A4 only if it is different from A1, A2, and A3?</p>
  
  <p>I hope that made sense. Thank you so much for your help!</p>