Posted just to see if it's what you are looking for, since it seems a little unclear (see other replies :) 

perl -ne '/^(?!.*(.)\1)(?=.*(.).+\2)(?=.*(?!\2)(.).+\3)\w{12}$/ and pr
+int' /usr/share/dict/words

[download]

This finds 2657 entries in my 'words' file with no adjacent duplicates but at least two different duplicated letters.

In reply to Re: Words, no consecutive doubled letters but repeated letters by tybalt89
in thread Words, no consecutive doubled letters but repeated letters by wlegrand

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