an class='st'>"Y"</span>,<span class='fl'>2</span><span class='op'>)</span>, <span class='fu'><a href='https://rdrr.io/r/base/rep.html'>rep</a></span><span class='op'>(</span><span class='st'>""</span>, <span class='fl'>2</span><span class='op'>)</span><span class='op'>)</span>,
                 AEDECOD <span class='op'>=</span> <span class='va'>letters</span><span class='op'>[</span><span class='fl'>1</span><span class='op'>:</span><span class='fl'>5</span><span class='op'>]</span>, AESTDTC <span class='op