a-a a-b a-c a-t aaa aab aac aak aao aar aat ab- aba abb abc abk abo abr abt ac- aca acb acc ack aco acr act aka akb akc akk ako akr aoa aob aoc aok aoo aor aot ar- ara arb arc ark aro arr art at- ata atb atc ato atr att baa bab bac bak bao bar bat bba bbb bbc bbk bbo bbr bbt bca bcb bcc bck bco bcr bct bka bkb bkc bkk bko bkr bkt boa bob boc bok boo bor bot bra brb brk bro brr brt bta btb btc btk bto btr btt c-- caa cab cac cak cao car cat cba cbb cbc cbk cbo cbr cbt cca ccb ccc cck cco ccr cct cka ckb ckc cko ckt co- coa cob coc cok coo cor cot cra crb crc crk cro crr crt cta ctb ctc ctk cto ctr ctt k-t ka- kaa kab kac kak kao kar kat kba kbb kbc kbk kbo kbr kca kcb kcc kck kcr kct kkb kkc kkk kkr kkt koa kob koc kok koo kor kot kra krc krk kro krr krt kta ktb ktc ktk kto ktr ktt oaa oab oac oak oao oar oat ob- oba obb obc obk obo obr obt oc- oca ocb occ ock oco ocr oct oka okb okc okk oko okr oo- ooa oob ooc ook ooo oor oot or- ora orb orc ork oro orr ort ot- ota otb otc otk oto otr ott ra- raa rab rac rak rao rar rat rba rbb rbc rbk rbo rbr rbt rca rcb rcc rco rcr rct rkb rkc rkk rko rkt roa rob roc rok roo ror rot rra rrb rrc rrk rrr rrt rta rtb rtc rtk rto rtr rtt taa tab tac tak tao tar tat tba tbb tbc tbk tbo tbr tbt tca tcb tcc tck tco tcr tct tka tkb tkc tkk tko tkr tkt to- toa tob toc tok too tor tot tra trb trc trk tro trr trt tta ttb ttc ttk tto ttr ttt

a-ak a-ok aaaa aaab aaac aaar aaba aabb aabc aabt aaca aacb aacc aack aaco aacr aact aaka aaoo aara aarc aaro aart aata aatc aatk aatt abaa abab abac abak abar abat abb- abba abbb abbo abbr abbt abca abcb abcc abcr abct aboa abob abok aboo abor abot abra abrc abro abta ac-t acaa acab acac acar acat acba acca accc acco acct acoa acor acot acr- acra acrc acro acrr acta actc acto actt akaa akao akar akca akka akko akok akot akr- akra aoba aoca aora aorb aort aotc arab arac arak arar arat arba arc- arca arco arct arka arko aroa arob aroo aror arr- arra arrc arrk arro arrr arrt arta artc arto artr at-t ataa atab atac atak atar atat atca atcc atck atco atcr atka atkt atob atoc atok ator atot atra atrc atrk atro atta atto attr baaa baak baar baat baba babb babo babr bac- baca bacc back baco bact bak- baka bako bakr bakt bar- bara barb barc bark baro barr bart bata batc bato batt bbbb bbrc bcaa bcar bcat bcbc bcca bccc bcor bcra bctc boab boac boak boar boat boba bobb bobo boca bock boco boka boko boob booc book boor boot bor- bora bork boro borr bort bota botb boto bott brab brac brak brao brat brca brcb brka brkb broa brob broc brok broo bror brot brrr brtc btaa btcc btob btor btrc btrt bttb c-bo caaa caab caac caat caba cabo cac- caca cacc cack caco cacr caka caor cara carb carc cark caro carr cart cat- cata catb catc cato catt cbac cbar cbat cbbc cbca cbcc cbcr cbct cbka cbko cbkr cbot cbrt cbta cbtc ccaa ccab ccac ccar ccat ccba ccbc ccca cccb cccc ccob ccoc ccra ccrc ccrt cctb cctc cctt ckac ckat ckbc ckck ckco ckoa ckob ckoc ckoo ckor ckot ckrc cktb coak coat coba cobb cobo coca cock coco coct cok- coka coko coob cook coot cor- cora corb corc cork coro corr cort cota cotb cotc coto cott crab crac crar crat crbc crca crcc crcr crkc crob croc crok croo cror crot crrt crtc ctab ctba ctca ctor ctot ctrc ctta kaaa kaab kaak kaar kaat kaba kabb kabc kabo kabr kacb kacc kaco kact kaka kakc kakk kako kakt kaoa kaoc kaok kaor kara karb kark karo karr kart kat- kata katb katc katk kato katr katt kbaa kbab kbac kbak kbar kbat kbba kbbb kbbc kbbk kbbo kbbr kbbt kbca kbcb kbck kbco kbcr kbct kbkb kbkk kbko kbkr kboa kbob kboc kbok kboo kbot kbra kbrb kbrc kbrk kbro kbrt kbta kbtb kbtc kbtk kbto kbtr kbtt kcaa kcab kcac kcar kcat kcba kcbc kcbk kcbr kcca kccb kccc kcck kccr kcct kckc kckk kcko kckr kcob kcor kcot kcrc kcro kcrr kcrt kcta kctb kctc kcto kkaa kkac kkar kkat kkba kkbb kkbo kkbr kkbt kkcb kkck kkco kkcr kkct kkkk kkoa kkob kkoo kkor kkot kkrb kkrc kkrk kkro kkrr kkrt kktc kktk koab koac koak koar koba kobb kobc kobk kobo kobr koca kocb kock koct koka kokb kokc kokk koko kokr koob kooc kook kooo koor koot kora korb korc kork koro korr kort kota kotb kotc kotk koto kotr kott krab krac krak krar krat krba krbb krbk krbr krbt krca krcb krcc krco krka krkc krkk krko krkr kroa krob kroc krok kroo kror krrb krrc krrk krro krrr krrt krta krtc krtk krto krtr ktaa ktak ktao ktar ktat ktba ktbb ktbc ktbr ktbt ktcc ktck ktco ktcr ktkb ktkc ktkk ktko ktkr ktkt ktob ktoc ktok ktoo ktor ktot ktrb ktrc ktrk ktro ktrr ktrt kttc kttk ktto kttr kttt oara obak obba obbo obkb obok obor obot obra obro ocab ocac ocak ocat ocbc occa occc occt ocra ocro ocrr oct- octa octo okak okka okko okok okor okot okra okro okta okto ooaa ooak