title: array formula is not working in google sheet
body: <p><strong>What I want to do:</strong></p>
  
  <ul>
  <li>Check if 4 of my cells are blank or not</li>
  <li>If all of them are not blank, then its okay, else display nothing ("")</li>
  <li>I want it to be auto dragged down </li>
  </ul>
  
  <p><strong>What I have tried</strong></p>
  
  <p><code>=arrayformula(if(AND(not(A1:D=""),not(B1:B=""),not(C1:C=""),not(D1:D="")),"ok",""))</code></p>
  
  <p><strong>Result</strong></p>
  
  <ul>
  <li>Although the statements of AND is true, it displays nothing ""</li>
  </ul>
  
  <p>What can be the issue in the formula?</p>