a-a a-b a-c aaa aab aac aaf aao aar aau ab- aba abb abc abf abo abr abu ac- aca acb acc acf aco acr acu af- afa afb afc aff afo afr afu aoa aob aoc aof aoo aor aou ar- ara arb arc arf aro arr aru au- aua aub auc auf auo aur b-u baa bab bac baf bao bar bau bba bbb bbc bbf bbo bbr bbu bca bcb bcc bcf bco bcr bcu bfa bfb bfc bff bfo bfr bfu boa bob boc bof boo bor bou bra brb brf bro brr bru bua bub buc buf buo bur buu c-- caa cab cac caf cao car cau cba cbb cbc cbf cbo cbr cbu cca ccb ccc ccf cco ccr ccu cfa cfb cfc cff cfo cfr cfu co- coa cob coc cof coo cor cou cra crb crc crf cro crr cru cua cub cuc cuf cuo cur cuu faa fab fac faf fao far fau fba fbb fbc fbf fbo fbr fbu fca fcb fcc fcf fco fcr fcu ffa ffc fff ffo ffr ffu foa fob foc fof foo for fou fra frb frc frf fro frr fru fua fub fuf fuo fur fuu oaa oab oac oaf oao oar oau ob- oba obb obc obf obo obr obu oc- oca ocb occ ocf oco ocr ocu of- ofa ofb ofc off ofo ofr ofu oo- ooa oob ooc oof ooo oor or- ora orb orc orf oro orr oru ou- oua ouc ouf ouo our ra- raa rab rac raf rao rar rau rba rbb rbc rbf rbo rbr rbu rca rcb rcc rcf rco rcr rcu rfa rfb rfc rff rfo rfr rfu roa rob roc rof roo ror rou rra rrb rrc rrf rrr rru rua rub ruc ruf ruo rur ruu ua- uaa uab uac uaf uao uar uau uba ubb ubc ubf ubo ubr ubu uca ucb ucc ucf uco ucr ucu ufa ufc uff ufo ufr ufu uoa uob uoc uoo uor ur- ura urb urc urf uro urr uru uua uuc uur uuu

a-fu aaaa aaab aaac aaaf aaar aaba aabb aabc aaca aacb aacc aacf aaco aacr aacu aafa aafb aafc aaff aaoo aara aarc aaro aaru abaa abab abac abaf abar abau abb- abba abbb abbo abbr abca abcb abcc abcf abcr abff aboa abob abof aboo abor abou abra abrc abro abua abuf acaa acab acac acar acba acca accc accf acco accu acfc acoa acor acou acr- acra acrc acro acrr acu- acuf acuo acur afaa afao afar afca afcb afcc afcu affa affc affo afoa afoo afor afr- afra afrc afro afru afua aoba aoca aora aorb aouf arab arac araf arar arau arba arc- arca arco arfa arfb arfc arff arfu aroa arob aroo aror arr- arra arrc arro arrr arru arua arub auaa auca aufc aur- aura auro baaa baaf baar baba babb babo babr babu bac- baca bacc baco bafc baff bafo bar- bara barb barc barf baro barr baru bau- bauf baur bbau bbbb bbfc bbrc bcaa bcar bcbc bcca bccc bcfc bcof bcor bcra bcru bcuc bfca boab boac boar boba bobb bobo bobu boca boco bocu bofa boff bofu boob booc boof boor bor- bora borf boro borr boru boua bouf bour brab brac braf brao brau brca brcb brfc brfu broa brob broc broo bror brou brrr bruc buar buba bubb bubo bubu buca bucc buco bucu bufc buff bufo bufr bur- bura burb buro burr buru c-bo caaa caab caac caaf caba cabf cabo cabu cac- caca cacc caco cacr cafa cafb cafc caff cafu caor cara carb carc carf caro carr cauc cauf cauo cbac cbar cbbc cbca cbcc cbcr cbcu cbfb cbfc ccaa ccab ccac ccaf ccar ccba ccbc ccca cccb cccc cccf cccu ccfa ccfc ccff ccob ccoc ccra ccrc ccrf ccuc cfaa cfab cfac cfao cfar cfbc cfbr cfca cfcb cfcf cfco cffb cffr cfoa cfor cfra cfrb coba cobb cobo cobu coca coco cocu cofc coff coob coof cor- cora corb corc corf coro corr coua coub cour crab crac craf crar crau crbc crbu crca crcc crcr crfc crob croc croo cror crub cuau cub- cuba cubb cuca cucc cufa cufc cuff cufo cura curb curf curo curr faaa faac faba fabo fabu faca facc fafa fafc faff fafo fara farb farc faro farr faru faur fbar fcab fcar fcba fcca fccf fcra ffar ffcc ffff ffrr foaf foar foba foca foco fofo foof for- fora forb foro forr foua four frab frac frau frbc frcc frfc frob frou frub fuar fubb fubu fuc- fuca fufc fuff fufu fuor fur- fura furo furr oaau oafc oafo oara obba obbo obor obra obro ocab ocac ocbc occa occc ocfa ocra ocro ocrr ocur ofcr off- offa offc offo offr offu ofor ofra ooaa ooba oocr ooff oooo oora orab orac orao orar orba orbb orbo orbu orca orco orff orfu oro- orof oror orra orro orub ouac oucc oufc ouff our- oura ouro ouu- raab raaf raba rabb rabo rabu rac- raca racc raco racu rafa rafc raff raob raoc rara rarb rarf raro raua raub rauc rauf rbaf rbbb rbbr rcac rcaf rcbc rcbo rccb rccc rcfc rffc roab roaf roar rob- roba robb robo robu roca rocc roco rofc roff rofo roob roof roor rora rorc roro roru roua roub rouf rrfc rrrr ruba rubb rubu ruca rufa rufc ruff rufo rura rurc ruro ruru uabc uaca uafa uaoc uarc uaru uaua ubac ubar ubba ubbo uboc ubra ucar ucbc ucca ucfa ucfb ucrc ucua ufcu uffa ufra uocc uofa uofo uor- urac urao urau urba urca urfa urff uro- uroa uroo urra urur uuoc uuuu

-aaa- aaaoc aaarc aabaa aabba aabra aacbc aacfo aarau abaab ababa ababu abaca abaco abara abaru abbac abbar abbou abbur abccc abfab aboab abobo abora aborc abrac abrar abura aburr acaca acacb acar- acara acaua accra accub accur acou- acoua acouo acrab acro- acrob acuba acuff acura afara