nler nlgn nlrb nngn nnnn nren nrlb nrrc nrrl nubc nube nubk nubl nuce nuck nucu nuee nuel nuer nuke nuku nule null nunc nune nung nunk nunn nurc nure nurl nurn nurr nuru nuuk rbbb rbbr rbcl rble rcbc rccb rccc rcgc rcle rcnl rcnr rcrg rebb rebe rebk rebu recc rece reck recr recu reeb reek reel reen rege regl regn regr regu reke relb rele rell rene reng renk renn renu rere rerg reru reue reuk reul reuu rgbe rlcg rlee rleu rlug rnbr rrle rrrr rrun rubb rube rubu ruce ruck ruel ruen ruer ruge rugg ruke rukk rukn ruku rule rulk rull runc rune rung runk runn rurc rure ruru ruun ubbe ubek uber uble ucbc ucel ucrc uele uell ugcc ugcg ugne ugur uguu ukcc ukek ukeu uknc ukrc ukur ulbc ulcc uleb ulee ulek ulen ulle ullr ulne uluk ulul unbe uncc unce uncg uncl uneb unec unee unen uner ungu unke unkl unkn unle unne urbe ure- urge urgu urke urle urne urre uruk urun urur uuen uulu uuuu