title: awk using filter less than 3 unique characters in column
body: <p>i have a dataset in file</p>
  <pre><code>1   AAA
  1   AAAB
  1   AAABC
  2   ABCD
  2   ABCDE
  3   AABB
  3   AABCD
  3   ABCDE
  3   ABBCCDE
  </code></pre>
  <p>Desired output</p>
  <pre><code>1   AAABC
  2   ABCD
  2   ABCDE
  3   AABCD
  3   ABCDE
  3   ABBCCDE
  </code></pre>
  <p>i have tried :</p>
  <pre><code>awk 'BEGIN{FS=&quot;\t&quot;; OFS=&quot;\t&quot;} {
  unq=0; delete seen; for (i=1; i&lt;=NF; i++) if (!seen[$i]++) unq++} unq &gt; 3' file
  </code></pre>
  <p>But i cant get any results.</p>