a-ak a-ok aaaa aaab aaac aaba aabb aabc aabt aaca aacb aacc aack aaco aact aaka aaoo aata aatc aatk aatt abaa abab abac abak abat abb- abba abbb abbo abbt abca abcb abcc abct aboa abob abok aboo abot abta ac-t acaa acab acac acat acba acca accc acco acct acoa acot acta actc acto actt akaa akao akca akka akko akok akot aoba aoca aotc at-t ataa atab atac atak atat atca atcc atck atco atka atkt atob atoc atok atot atta atto baaa baak baat baba babb babo bac- baca bacc back baco bact bak- baka bako bakt bata batc bato batt bbbb bcaa bcat bcbc bcca bccc bctc boab boac boak boat boba bobb bobo boca bock boco boka boko boob booc book boot bota botb boto bott btaa btcc btob bttb c-bo caaa caab caac caat caba cabo cac- caca cacc cack caco caka cat- cata catb catc cato catt cbac cbat cbbc cbca cbcc cbct cbka cbko cbot cbta cbtc ccaa ccab ccac ccat ccba ccbc ccca cccb cccc ccob ccoc cctb cctc cctt ckac ckat ckbc ckck ckco ckoa ckob ckoc ckoo ckot cktb coak coat coba cobb cobo coca cock coco coct cok- coka coko coob cook coot cota cotb cotc coto cott ctab ctba ctca ctot ctta kaaa kaab kaak kaat kaba kabb kabc kabo kacb kacc kaco kact kaka kakc kakk kako kakt kaoa kaoc kaok kat- kata katb katc katk kato katt kbaa kbab kbac kbak kbat kbba kbbb kbbc kbbk kbbo kbbt kbca kbcb kbck kbco kbct kbkb kbkk kbko kboa kbob kboc kbok kboo kbot kbta kbtb kbtc kbtk kbto kbtt kcaa kcab kcac kcat kcba kcbc kcbk kcca kccb kccc kcck kcct kckc kckk kcko kcob kcot kcta kctb kctc kcto kkaa kkac kkat kkba kkbb kkbo kkbt kkcb kkck kkco kkct kkkk kkoa kkob kkoo kkot kktc kktk koab koac koak koba kobb kobc kobk kobo koca kocb kock koct koka kokb kokc kokk koko koob kooc kook kooo koot kota kotb kotc kotk koto kott ktaa ktak ktao ktat ktba ktbb ktbc ktbt ktcc ktck ktco ktkb ktkc ktkk ktko ktkt ktob ktoc ktok ktoo ktot kttc kttk ktto kttt obak obba obbo obkb obok obot ocab ocac ocak ocat ocbc occa occc occt oct- octa octo okak okka okko okok okot okta okto ooaa ooak ooba oooo ootb otac otak oto- otok otoo otta otto taa- taat taba tabb tabc tabo taca tacc tack taco tact taka takk tako takt taoa tata tatb tato tatt tbca tbcb tbcc tbta tcca tccc tctc tkac toab toat toba tobo tobt toca tock toco toka toko tooa took toot tota totc toto tott ttab ttbb tttt