-er a-a a-b a-c aaa aab aac aae aag aak aao aar ab- aba abb abc abe abg abk abo abr ac- aca acb acc ace acg ack aco acr aea aeb aec aee aeg aek aeo aer ag- aga agb agc age agg agk ago agr aka akb akc ake akg akk ako akr aoa aob aoc aoe aog aok aoo aor ar- ara arb arc are arg ark aro arr baa bab bac bae bag bak bao bar bba bbb bbc bbe bbg bbk bbo bbr bca bcb bcc bce bcg bck bco bcr be- bea beb bec bee beg bek beo ber bga bgb bgc bge bgg bgk bgo bgr bka bkb bkc bke bkg bkk bko bkr boa bob boc boe bog bok boo bor bra brb bre brg brk bro brr c-- caa cab cac cae cag cak cao car cba cbb cbc cbe cbg cbk cbo cbr cca ccb ccc cce ccg cck cco ccr ce- cea ceb cec cee ceg cek ceo cer cga cgb cgc cge cgg cgo cgr cka ckb ckc cko co- coa cob coc coe cog cok coo cor cra crb crc cre crg crk cro crr eaa eab eac eae eag eak eao ear eba ebb ebc ebe ebg ebk ebo ebr ec- eca ecb ecc ece ecg eck eco ecr eea eeb eec eee eeg eek eeo eer ega egb egc ege egg ego egr eka ekb ekc eke ekg eko ekr eo- eoa eob eoc eoe eog eok eoo eor era erb erc ere erg erk ero err gaa gab gac gae gag gak gao gar gba gbc gbe gbg gbk gbo gbr gca gcb gcc gce gcg gck gco gcr ge- gea geb gec gee geg gek geo ger gga ggb ggc ggg ggo ggr gka gkb gko goa gob goc goe gog gok goo gor gra grb grc gre grg grk gro grr ka- kaa kab kac kae kag kak kao kar kba kbb kbc kbe kbk kbo kbr kca kcb kcc kce kcg kck kcr ke- kea keb kec kee keg kek keo ker kga kgb kgc kgo kkb kkc kke kkk kkr koa kob koc koe kog kok koo kor kra krc krg krk kro krr oaa oab oac oae oag oak oao oar ob- oba obb obc obe obg obk obo obr oc- oca ocb occ ocg ock oco ocr oea oeb oec oee oeg oeo oer oga ogc oge ogg ogo oka okb okc oke okg okk oko okr oo- ooa oob ooc oog ook ooo oor or- ora orb orc ore org ork oro orr ra- raa rab rac rae rag rak rao rar rba rbb rbc rbe rbg rbk rbo rbr rca rcb rcc rce rcg rco rcr re- rea reb rec ree reg rek reo rer rga rgb rgc rge rgg rgk rgo rgr rkb rkc rke rkg rkk rko roa rob roc roe rog rok roo ror rra rrb rrc rrg rrk rrr

a-ak a-be a-ok aaaa aaab aaac aaae aaar aaba aabb aabc aaca aacb aacc aace aack aaco aacr aaea aaec aage aaka aake aaoe aaoo aara aarc aare aaro abaa abab abac abae abag abak abar abb- abba abbb abbe abbo abbr abca abcb abcc abcr abec abee aber aboa abob abok aboo abor abra abrc abro acaa acab acac acae acag acar acba acca accc acce acco ace- acea acec acek acer acga acgr acke acoa acoe acog acor acr- acra acrc acre acro acrr aeac aecb aeer aega aeka aer- aera aerc aero ag-o agac agag agao agar agba agbo agca agcc agce agco agea agee ager agga agge agob agog agoo agra agre agro akaa akae akao akar akca akee akeg aker akka akko akok akr- akra akre aoba aoca aoce aora aorb arab arac arae arag arak arar arba arbe arc- arca arce arco area arec aree areg arek areo arga argb arge argo arka arke arko aroa arob aroe aroo aror arr- arra arrc arre arrg arrk arro arrr baaa baak baar baba babb babe babo babr bac- baca bacc bace back baco baek baer baga bage bagg bago bak- baka bake bako bakr bar- bara barb barc bare barg bark baro barr bbbb bbeb bbga bbrc bbrg bcaa bcar bcbc bcbg bcca bccc bcec bcer bcor bcra beag beak bear beba bebb bebe bebo beca beck beeb beeg beek beer bega begg bego beka beke beko beo- beok beor bera berc bere berg berk bero berr bgca boab boac boag boak boar boba bobb bobe bobo boca boce bock boco boea boec boee boeo boer boga boge bogg bogo boka boke boko boob booc booe boog book boor bor- bora bore borg bork boro borr brab brac brae brag brak brao brca brcb brce brea breb brec bree breg brek breo brer brka brkb broa brob broc broe brog brok broo bror brrr c-bo caaa caab caac caba cabe cabg cabo cac- caca cacc cace cack caco cacr caec caer caga cage cagg cago cagr caka cake caor cara carb carc care cark caro carr cbac cbar cbbc cbca cbcc cbce cbcr cbea cbec cbee cber cbga cbgb cbka cbkg cbko cbkr cbre ccaa ccab ccac ccag ccar ccba ccbc ccca cccb cccc ccee ccga ccgc ccob ccoc ccra ccrc ccre ccrg ceac cear ceba cec- ceca cece ceco ceeb ceec cege cego ceke ceor cer- cera cerc cere cero cgac cgcc cgcg cger cgro ckac ckbc ckbe ckck ckco cker ckga ckgo ckoa ckob ckoc ckoo ckor ckrc coag coak coba cobb cobe cobo coca coce cock coco cogo cok- coka coke coko coob cook cor- cora corb corc core corg cork coro corr crab crac crag crar crbc crca crcc crce crcr cre- crea creb crec cree creg creo crkc crob croc croe crok croo cror eaba eaca eacc eaec eaga eage eara earb eare earo ebac ebba ebbc ebbo ebbr ebcc eber eboe eboo ebor ebro ecaa ecac ecao ecar ecbc ecbe ecca eccb