-ic a-a a-b a-c a-i aaa aab aac aag aai aak aar ab- aba abb abc abg abi abk abr ac- aca acb acc acg aci ack acr ag- aga agb agc agg agi agk agr ai- aia aib aic aig aii aik air aka akb akc akg aki akk akr ar- ara arb arc arg ari ark arr baa bab bac bag bai bak bar bba bbb bbc bbg bbi bbk bbr bca bcb bcc bcg bci bck bcr bga bgb bgc bgg bgi bgk bgr bi- bia bib bic big bii bik bir bka bkb bkc bkg bkk bkr bra brb brg bri brk brr c-- caa cab cac cag cai cak car cba cbb cbc cbg cbi cbk cbr cca ccb ccc ccg cci cck ccr cga cgb cgc cgg cgi cgr ci- cia cib cic cig cii cik cir cka ckb ckc cki cra crb crc crg cri crk crr gaa gab gac gag gai gak gar gba gbc gbg gbi gbk gbr gca gcb gcc gcg gci gck gcr gga ggb ggc ggg ggi ggr gia gib gic gig gii gik gir gka gkb gra grb grc grg gri grk grr ia- iaa iab iac iag iai iar iba ibb ibc ibg ibi ibk ibr ica icb icc icg ici ick icr iga igb igc igg igi igk igr iia iib iic iii iir ika ikb ikc iki ikk ikr ir- ira irb irc irg iri irk irr ka- kaa kab kac kag kai kak kar kba kbb kbc kbi kbk kbr kca kcb kcc kcg kci kck kcr kga kgb kgc kgi kia kib kic kig kii kik kir kkb kkc kki kkk kkr kra krc krg kri krk krr ra- raa rab rac rag rai rak rar rba rbb rbc rbg rbi rbk rbr rca rcb rcc rcg rci rcr rga rgb rgc rgg rgi rgk rgr ria rib ric rig rii rik rir rkb rkc rkg rkk rra rrb rrc rrg rri rrk rrr

a-ak a-ii aaaa aaab aaac aaai aaar aaba aabb aabc aabi aaca aacb aacc aaci aack aacr aaib aaic aaii aaka aara aarc aari abaa abab abac abag abai abak abar abb- abba abbb abbi abbr abca abcb abcc abci abcr abia abib abic abig abir abra abrc abri acaa acab acac acag acai acar acba acca accc acci acga acgi acgr aci- acia acic acir acr- acra acrc acri acrr agac agag agai agar agba agca agcc agga aggi agia agib agic agig agii agir agra agri aiai aiba aica aicc aicr aiga aiia aiib aiic aiir aika aiki aira airi akaa akai akar akca akia akik akir akka akki akr- akra arab arac arag arai arak arar arba arbi arc- arca arci arga argb argi aria arib arig arii arik arka arki arr- arra arrc arrg arri arrk arrr ba-i baaa baak baar baba babb babi babr bac- baca bacc baci back baga bagg bagi baia baib baic baig baik bair bak- baka baki bakr bar- bara barb barc barg bari bark barr bbbb bbci bbga bbrc bbrg bcaa bcar bcbc bcbg bcca bccc bcci bcia bcra bgca bgia biak biar biba bibb bibi bica bicc bicg bici bick biga bigb bigc bigg bira birb birg biri birk birr brab brac brag brai brak brca brcb bria bric brig brik brka brkb brrr caaa caab caac caba cabg cabi cac- caca cacc caci cack cacr caga cagg cagi cagr caia caib caic caik cair caka cara carb carc cari cark carr cbac cbar cbbc cbca cbcc cbcr cbga cbgb cbia cbir cbka cbkg cbkr ccaa ccab ccac ccag ccai ccar ccba ccbc ccca cccb cccc ccci ccga ccgc ccic ccii ccir ccra ccrc ccrg ccri cgac cgcc cgcg ciaa ciak ciar ciba cibc cibi cica cicc cici cicr ciga cigi ciia ciii cika cikr cira cirb circ ciri cirk cirr ckac ckbc ckbi ckck ckga ckrc crab crac crag crai crar crbc crca crcc crcr cria crib cric crig crik crkc gaar gaba gabb gabi gabr gack gaga gagg gagi gaia gaig gair gaki gara garb garg gari garr gbag gc-c gcaa gcbc gccc gcic gcii gcrg gggg giaa giac giai giba gibb gica gick gicr giga gigg gigi gira girg giri girk girr grab grac grai grbr grcc gria grib gric grig grrr iaaa iaac iaai iaba iaca iacc iacr iaia iara iarc ibac ibar ibca ibga ibia ibra ibrc ibri icaa icab icac icag icai icar icbc icca iccb iccc icci iccr icga icgc icra icrc icrr igac igar igba igbc igcc igga igia igkc igra igri iiac iica iiii iira iirc ikar ikig ikki ikra ikri irac irai irak irar irca ircc ircg iri- iria iric irig irka irki irra irrc irri k-ci kaaa kaab kaag kaai kaak kaar kaba kabb kabc kabg kabi kabr kacb kacc kaci kag- kaga kagb kagc kagg kagi kagr kaia kaib kaic kaig kaii kaik kair kaka kakc kaki kakk kara karb karg kari kark karr kbaa kbab kbac kbai kbak kbar kbba kbbb kbbc kbbg kbbi kbbk kbbr kbca kbcb kbci kbck kbcr kbga kbgb kbgg kbgr kbia kbib kbic kbig kbik kbkb kbkg kbkk kbkr kbra kbrb kbrc kbrg kbri kbrk kcaa kcab kcac kcai kcar kcba kcbc kcbi kcbk kcbr kcca kccb kccc kcci kcck kccr kcgc kcgi kcgr kcic kcii kcir kckc kckk kckr kcrc kcrg kcri kcrr kgab kgac kgak kgba kgbb kgbc kgbr kgcb kgcc kgcr kgga kggg kggi kggr kgia kgir kgra kgrb kgrc kgrg kgri kgrk kgrr kiab kiac kiai kiar kiba kibb kibc kibg kibi kibr kica kicb kicc kicg kick kicr kiga kigc kiia kiic kiii kiik kika kikc kiki kikk kikr kira kirb kirc kiri kirk kirr kkaa kkac kkag kkai kkar kkba kkbb kkbg kkbi kkbr kkcb kkci kkck kkcr kkgb kkgr kkia kkic kkik kkkk kkrb kkrc kkrk kkrr krab krac krag krai krak krar krba krbb krbg krbi krbk krbr krca krcb krcc krcg krci krgi kria krib krik krka krkc krki krkk