aaaa aaab aaac aaar aaba aabb aabc aabt aaca aacb aacc aacr aact aacu aara aarc aart aaru aata aatc aatt abaa abab abac abar abat abau abb- abba abbb abbr abbt abca abcb abcc abcr abct abra abrc abta abtu abua abut ac-t acaa acab acac acar acat acba acca accc acct accu acr- acra acrc acrr acta actc actt actu acu- acur acut arab arac arar arat arau arba arc- arca arct arr- arra arrc arrr arrt arru arta artc artr arua arub arut at-t ataa atab atac atar atat atca atcc atcr atra atrc atru atta attr attu atua atub atuc atur auaa auca auct aur- aura aut- baaa baar baat baba babb babr babu bac- baca bacc bact bar- bara barb barc barr bart baru bata batc batt batu bau- baur bbau bbbb bbrc bcaa bcar bcat bcbc bcca bccc bcra bcru bctc bcuc brab brac brat brau brca brcb brrr brtc bruc brut btaa btcc btrc btrt bttb buar buat buba bubb bubu buca bucc bucu bur- bura burb burr burt buru but- buta butt caaa caab caac caat caba cabu cac- caca cacc cacr cara carb carc carr cart cat- cata catb catc catt catu cauc caut cbac cbar cbat cbbc cbca cbcc cbcr cbct cbcu cbrt cbta cbtc ccaa ccab ccac ccar ccat ccba ccbc ccca cccb cccc cccu ccra ccrc ccrt cctb cctc cctt ccuc ccut crab crac crar crat crau crbc crbu crca crcc crcr crrt crtc crub crut ctab ctba ctca ctrc ctta cuau cub- cuba cubb cuca cucc cura curb curr curt cut- cuta cutc cutt raab raat raba rabb rabu rac- raca racc ract racu rara rarb rata ratt ratu raua raub rauc raut rbbb rbbr rcac rcbc rccb rccc rctc rrat rrrr rtca rtcc ruba rubb rubu ruca ruct rura rurc ruru ruta rutt rutu taa- taar taat taba tabb tabc tabu taca tacc tact tara tarb tarc tarr tart taru tata tatb tatr tatt tatu taua taub tauc taur taut tbar tbca tbcb tbcc tbrb tbta tcca tccc tccu tctc traa trab trac trat trau trca trcc trra trtc trtr trub truc trut truu ttab ttbb tttt tuar tuat tuba tubb tubr tubu tuca tucc tura turb turc turr turt turu tuta tutt tutu uabc uaca uarc uart uaru uata uatu uaua ubac ubar ubba ubra ucar ucat ucbc ucca ucrc ucua ucut urac urat urau urba urca urra urur urut utac utau uttu uuta uuuu