-er a-a a-b a-c a-t aaa aab aac aae aak aar aat aax ab- aba abb abc abe abk abr abt abx ac- aca acb acc ace ack acr act acx aea aeb aec aee aek aer aet aex aka akb akc ake akk akr ar- ara arb arc are ark arr art arx at- ata atb atc ate atr att atx ax- axa axe axk axr axt axx baa bab bac bae bak bar bat bax bba bbb bbc bbe bbk bbr bbt bbx bca bcb bcc bce bck bcr bct bcx be- bea beb bec bee bek ber bet bex bka bkb bkc bke bkk bkr bkt bkx bra brb bre brk brr brt brx bta btb btc bte btk btr btt btx bxb bxx c-- caa cab cac cae cak car cat cax cba cbb cbc cbe cbk cbr cbt cbx cca ccb ccc cce cck ccr cct ccx ce- cea ceb cec cee cek cer cet cex cka ckb ckc ckt ckx cra crb crc cre crk crr crt crx cta ctb ctc cte ctk ctr ctt ctx cxc cxk cxr cxt cxx eaa eab eac eae eak ear eat eax eba ebb ebc ebe ebk ebr ebt ebx ec- eca ecb ecc ece eck ecr ect ecx eea eeb eec eee eek eer eet eex eka ekb ekc eke ekr ekt era erb erc ere erk err ert eta etb etc ete etk etr ett etx ex- exa exc exe exr ext exx k-t ka- kaa kab kac kae kak kar kat kax kba kbb kbc kbe kbk kbr kbx kca kcb kcc kce kck kcr kct kcx ke- kea keb kec kee kek ker ket kex kkb kkc kke kkk kkr kkt kra krc krk krr krt kta ktb ktc kte ktk ktr ktt ra- raa rab rac rae rak rar rat rax rba rbb rbc rbe rbk rbr rbt rbx rca rcb rcc rce rcr rct rcx re- rea reb rec ree rek rer ret rex rkb rkc rke rkk rkt rra rrb rrc rrk rrr rrt rta rtb rtc rte rtk rtr rtt rtx rxr t-x taa tab tac tae tak tar tat tax tba tbb tbc tbe tbk tbr tbt tca tcb tcc tce tck tcr tct tcx te- tea teb tec tee tek ter tet tex tka tkb tkc tke tkk tkr tkt tra trb trc tre trk trr trt trx tta ttb ttc tte ttk ttr ttt ttx txe txk txt xaa xac xak xar xat xbc xbe xbr xbx xcb xcr xcx xee xer xet xex xkb xke xrc xrt xrx xtc xtr xtx xxx

a-ak a-be aaaa aaab aaac aaae aaar aaba aabb aabc aabt aaca aacb aacc aace aack aacr aact aaea aaec aaka aake aara aarc aare aart aata aatc aatk aatt abaa abab abac abae abak abar abat abax abb- abba abbb abbe abbr abbt abca abcb abcc abcr abct abec abee aber abet abra abrc abta ac-t acaa acab acac acae acar acat acba acca accc acce acct ace- acea acec acek acer acet acke acr- acra acrc acre acrr acta actc acte actt aeac aecb aect aeer aeka aer- aera aerc aeta aetc aetr aett aetx akaa akae akar akca akee aker akka akr- akra akre akte arab arac arae arak arar arat arax arba arbe arc- arca arce arct area arec aree arek aret arex arka arke arr- arra arrc arre arrk arrr arrt arta artc arte artr artx at-t at-x ataa atab atac atae atak atar atat atax atca atcc atck atcr atea atec atee ater atex atka atkt atra atrc atre atrk atrx atta atte attr axar axat axce axer ba-x baaa baak baar baat baba babb babe babr bac- baca bacc bace back bact baek baer bak- baka bake bakr bakt bar- bara barb barc bare bark barr bart barx bata batc bate batt baxt bbbb bbeb bbet bbrc bcaa bcar bcat bcbc bcca bccc bcec bcer bcet bcra bctc beak bear beat beba bebb bebe beca beck beeb beek beer beet beka beke bera berc bere berk berr bert beta betc bete bett brab brac brae brak brat brax brca brcb brce brea breb brec bree brek brer bret brex brka brkb brrr brtc btaa btcc btcx btec btek btex btrc btrt bttb caaa caab caac caat caba cabe cac- caca cacc cace cack cacr caec caer caex caka cake cara carb carc care cark carr cart carx cat- cata catb catc cate catt caxa cbac cbar cbat cbax cbbc cbca cbcc cbce cbcr cbct cbea cbec cbee cber cbet cbka cbkr cbre cbrt cbta cbtc cbxa ccaa ccab ccac ccar ccat ccba ccbc ccca cccb cccc ccee ccra ccrc ccre ccrt cctb cctc cctt ceac cear ceat ceba cec- ceca cece cect ceeb ceec ceke cer- cera cerc cere cert cet- ceta cete cexe ckac ckat ckbc ckbe ckbx ckck ckcx cker ckrc cktb crab crac crar crat crax crbc crca crcc crce crcr cre- crea creb crec cree cret crex crkc crrt crtc ctab ctae ctba ctca ctec ctrc ctta cxxx eaba eaca eacc eaec eara earb eare eart eata eate ebac ebba ebbc ebbr ebcc eber ecaa ecac ecar ecat ecbc ecbe ecca eccb eccc ecce ecct ecka ecra ecrc ecrr ect- ecta ectc eeca eeea eeee eeka eeke eera eerc eeta eetc eete eext eka- ekab ekeb ekek eker eket ekka ekta er-x erat erba erbb erbe erca ercc erce ereb erec erer eret erke erra errc erre erta etak etat etbc etbr etcc etec etee eter etka etra etre etta ette exa- exec exer exrx exta exte extr kaaa kaab kaak kaar kaat kaba kabb kabc kabe kabr kacb kacc kace kact kaer kaet kaka kakc kake kakk kakt kakx kara karb kare kark karr kart karx kat- kata katb katc kate katk katr katt katx kaxa kaxe kbaa kbab kbac kbae kbak kbar kbat kbba kbbb kbbc kbbe kbbk kbbr kbbt kbca kbcb kbce kbck kbcr kbct kbeb kbec kbee kbek