a-a a-b a-c aaa aab aac aak aao aar aav ab- aba abb abc abk abo abr abv ac- aca acb acc ack aco acr acv aka akb akc akk ako akr akv aoa aob aoc aok aoo aor aov ar- ara arb arc ark aro arr arv av- ava avb avc avk avo avr baa bab bac bak bao bar bav bba bbb bbc bbk bbo bbr bca bcb bcc bck bco bcr bcv bka bkb bkc bkk bko bkr bkv boa bob boc bok boo bor bov bra brb brk bro brr brv bva bvb bvc bvk bvo bvr bvv c-- caa cab cac cak cao car cav cba cbb cbc cbk cbo cbr cbv cca ccb ccc cck cco ccr ccv cka ckb ckc cko co- coa cob coc cok coo cor cov cra crb crc crk cro crr crv cva cvb cvc cvk cvo cvr cvv ka- kaa kab kac kak kao kar kav kba kbb kbc kbk kbo kbr kca kcb kcc kck kcr kkb kkc kkk kkr kkv koa kob koc kok koo kor kra krc krk kro krr krv kva kvb kvk kvo kvr kvv oaa oab oac oak oao oar oav ob- oba obb obc obk obo obr obv oc- oca ocb occ ock oco ocr ocv oka okb okc okk oko okr oo- ooa oob ooc ook ooo oor oov or- ora orb orc ork oro orr orv ov- ova ovb ovc ovo ovv ra- raa rab rac rak rao rar rav rba rbb rbc rbk rbo rbr rca rcb rcc rco rcr rcv rkb rkc rkk rko rkv roa rob roc rok roo ror rov rra rrb rrc rrk rrr rva rvb rvc rvo rvr rvv v-a vaa vab vac vak vao var vav vba vbc vbk vbo vbr vbv vca vcc vco vcr vka vkb voa vob voc vok voo vor vov vra vrb vrc vrk vrr vva vvb vvc vvo vvr vvv

-vac a-ak a-ok aaaa aaab aaac aaar aaav aaba aabb aabc aaca aacb aacc aack aaco aacr aacv aaka aaoo aara aarc aaro aava abaa abab abac abak abar abb- abba abbb abbo abbr abca abcb abcc abcr aboa abob abok aboo abor abov abra abrc abro abva acaa acab acac acar acba acca accc acco acoa acor acr- acra acrc acro acrr acrv acvv akaa akao akar akca akka akko akok akr- akra aoba aoca aora aorb arab arac arak arar arba arc- arca arco arka arko aroa arob aroo aror arr- arra arrc arrk arro arrr arva arvo avab avao avar avcc avco avor avra avro avva avvo baaa baak baar baba babb babo babr bac- baca bacc back baco bak- baka bako bakr bar- bara barb barc bark baro barr bava bbbb bbrc bcaa bcar bcbc bcca bccc bcor bcra bcvo boab boac boak boar boba bobb bobo boca bock boco boka boko boob booc book boor bor- bora bork boro borr bova bovo brab brac brak brao brav brca brcb brka brkb broa brob broc brok broo bror brrr c-bo caaa caab caac caba cabo cac- caca cacc cack caco cacr caka caor cara carb carc cark caro carr cava cavo cbac cbar cbbc cbca cbcc cbcr cbka cbko cbkr cbva cbvb cbvr ccaa ccab ccac ccar ccba ccbc ccca cccb cccc cccv ccob ccoc ccra ccrc ccvo ckac ckbc ckck ckco ckcv ckoa ckob ckoc ckoo ckor ckrc ckvo coak coba cobb cobo coca cock coco cok- coka coko coob cook cor- cora corb corc cork coro corr cova covo crab crac crar crbc crca crcc crcr crkc crob croc crok croo cror cvac cvar cvca cvcc cvra cvrr kaaa kaab kaak kaar kaba kabb kabc kabo kabr kacb kacc kaco kacv kaka kakc kakk kako kaoa kaoc kaok kaor kara karb kark karo karr karv kava kavb kavo kavv kbaa kbab kbac kbak kbar kbba kbbb kbbc kbbk kbbo kbbr kbca kbcb kbck kbco kbcr kbkb kbkk kbko kbkr kbkv kboa kbob kboc kbok kboo kbov kbra kbrb kbrc kbrk kbro kbrv kbva kbvb kbvc kbvo kbvr kcaa kcab kcac kcar kcav kcba kcbc kcbk kcbr kcca kccb kccc kcck kccr kccv kckc kckk kcko kckr kckv kcob kcor kcrc kcro kcrr kcrv kcvk kcvo kcvr kcvv kkaa kkac kkar kkba kkbb kkbo kkbr kkcb kkck kkco kkcr kkkk kkoa kkob kkoo kkor kkov kkrb kkrc kkrk kkro kkrr kkrv kkvr kkvv koab koac koak koar koba kobb kobc kobk kobo kobr koca kocb kock koka kokb kokc kokk koko kokr koob kooc kook kooo koor koov kora korb korc kork koro korr korv kova kovc kovk kovo kovr krab krac krak krar krav krba krbb krbk krbr krca krcb krcc krco krka krkc krkk krko krkr krkv kroa krob kroc krok kroo kror krov krrb krrc krrk krro krrr krva krvb krvc krvk krvo krvr krvv kvab kvak kvar kvbc kvbr kvcb kvcc kvck kvco kvcr kvcv kvoa kvob kvoc kvok kvoo kvor kvov kvra kvrc kvro kvrr kvrv kvvr kvvv oara obak obba obbo obkb obok obor obra obro ocab ocac ocak ocbc occa occc ocra ocro ocrr okak okka okko okok okor okra okro ooaa ooak ooba oocr oooo oora orab orac orak orao orar orav orba orbb orbo orca orco orka orko oro- orok oror orra orro orvr ovar ovo- ovoo ovra raab raak raba rabb rabk rabo rac- raca racc rack raco racv raka rakk raob raoc raok rara rarb rark raro rava rbbb rbbr rcac rcbc rcbo rccb rccc rcvr roab roak roar rob- roba robb robo roca rocc rock roco roka rokk roko rokr roob rook roor rora rorc rork roro rova rovo rrrr rv-c rvca vaar vaca vack vaco vaka vara vark varr vava vbcc vkor voar voca voka vooc voor vor- vora voro vovk vrac vrak vrav vrba vroc vvob vvvv

-aaa- aaaoc aaarc aabaa aabba aabra aacbc aakko abaab ababa abaca aback abaco abaka abako abara abava abbac abbar abccc abkar abkoo aboab abobo abook abora aborc abovo abrac abrak