-er a-a a-b a-c aaa aab aac aae aak aao aap aar ab- aba abb abc abe abk abo abp abr ac- aca acb acc ace ack aco acp acr aea aeb aec aee aek aeo aep aer aka akb akc ake akk ako akp akr aoa aob aoc aoe aok aoo aop aor ap- apa apb apc ape apk apo app apr ar- ara arb arc are ark aro arp arr b-p baa bab bac bae bak bao bap bar bba bbb bbc bbe bbk bbo bbp bbr bca bcb bcc bce bck bco bcp bcr be- bea beb bec bee bek beo bep ber bka bkb bkc bke bkk bko bkp bkr boa bob boc boe bok boo bop bor bpa bpb bpc bpe bpo bpp bpr bra brb bre brk bro brp brr c-- caa cab cac cae cak cao cap car cba cbb cbc cbe cbk cbo cbp cbr cca ccb ccc cce cck cco ccp ccr ce- cea ceb cec cee cek ceo cep cer cka ckb ckc cko co- coa cob coc coe cok coo cop cor cpa cpb cpc cpe cpk cpo cpp cpr cra crb crc cre crk cro crp crr eaa eab eac eae eak eao eap ear eba ebb ebc ebe ebk ebo ebp ebr ec- eca ecb ecc ece eck eco ecr eea eeb eec eee eek eeo eep eer eka ekb ekc eke eko ekp ekr eo- eoa eob eoc eoe eok eoo eop eor ep- epa epb epc epe epo epp epr era erb erc ere erk ero erp err ka- kaa kab kac kae kak kao kap kar kba kbb kbc kbe kbk kbo kbp kbr kca kcb kcc kce kck kcp kcr ke- kea keb kec kee kek keo kep ker kkb kkc kke kkk kkp kkr koa kob koc koe kok koo kop kor kpa kpc kpe kpk kpo kpp kpr kra krc krk kro krp krr oaa oab oac oae oak oao oap oar ob- oba obb obc obe obk obo obp obr oc- oca ocb occ ock oco ocp ocr oea oeb oec oee oeo oep oer oka okb okc oke okk oko okp okr oo- ooa oob ooc ook ooo oop oor op- opa opb opc ope opk opo opp opr or- ora orb orc ore ork oro orp orr p-p paa pab pac pae pak pao pap par pba pbb pbc pbe pbk pbo pbp pbr pca pcb pcc pce pck pco pcp pcr pea peb pec pee pek peo pep per pka pkb pkc pke pko pkp pkr poa pob poc poe pok poo pop por ppa ppb ppc ppe ppk ppo ppp ppr pra prb prc pre prk pro prp prr ra- raa rab rac rae rak rao rap rar rba rbb rbc rbe rbk rbo rbp rbr rca rcb rcc rce rco rcp rcr re- rea reb rec ree rek reo rep rer rkb rkc rke rkk rko rkp roa rob roc roe rok roo rop ror rpa rpb rpc rpe rpk rpo rpp rpr rra rrb rrc rrk rrp rrr

a-ak a-be a-ok aaaa aaab aaac aaae aaap aaar aaba aabb aabc aabp aaca aacb aacc aace aack aaco aacp aacr aaea aaec aaep aaka aake aaoe aaoo aapa aapc aapo aara aarc aare aaro aarp abaa abab abac abae abak abap abar abb- abba abbb abbe abbo abbr abca abcb abcc abcp abcr abec abee aber aboa abob abok aboo abor abpa abpc abpp abpr abra abrc abro acaa acab acac acae acap acar acba acca accc acce acco accp ace- acea acec acek acer acke acoa acoe acop acor acpa acpe acpr acr- acra acrc acre acro acrr aeac aeap aecb aeer aeka aer- aera aerc aero akaa akae akao akap akar akca akee aker akka akko akok akpo akr- akra akre aoba aoca aoce aokp aopo aora aorb apac apak apao apap apar apba apbr apca apcb apcc apco apcr apea apec apep aper apke apo- apoc apoe apoo apop apor appa appc appr apra aprc apre apro arab arac arae arak arap arar arba arbe arc- arca arce arco area arec aree arek areo arep arka arke arko aroa arob aroe aroo aror arpa arpe arr- arra arrc arre arrk arro arrr baaa baak baar baba babb babe babo babr bac- baca bacc bace back baco baek baer bak- baka bake bako bakr bapa bapc bape bapp bar- bara barb barc bare bark baro barr bbbb bbeb bbpr bbrc bcaa bcap bcar bcbc bcbp bcca bccc bcec bcer bcor bcpp bcra beak beap bear beba bebb bebe bebo beca beck beeb beek beep beer beka beke beko beo- beok beor bepo bera berc bere berk bero berr bkpr boab boac boak boar boba bobb bobe bobo boca boce bock boco boea boec boee boeo boep boer boka boke boko boob booc booe book boop boor bopa bope bopp bor- bora bore bork boro borr bpcp bpea bpoe bprc brab brac brae brak brao brca brcb brce brea breb brec bree brek breo brep brer brka brkb broa brob broc broe brok broo bror brrr c-bo caaa caab caac caap caba cabe cabo cac- caca cacc cace cack caco cacr caec caer caka cake caor capa capb capc cape capo capp cara carb carc care cark caro carp carr cbac cbar cbbc cbca cbcc cbce cbcp cbcr cbea cbec cbee cber cbka cbko cbkr cbpc cbpp cbre ccaa ccab ccac ccap ccar ccba ccbc ccca cccb cccc cccp ccee ccob ccoc ccpa ccpe ccpp ccpr ccra ccrc ccre ccrp ceac cear ceba cebp cec- ceca cece ceco cecp ceeb ceec ceke ceop ceor cepa cepc cepe cepo cepp cepr cer- cera cerc cere cero cerp ckac ckbc ckbe ckck ckco cker ckoa ckob ckoc ckoo ckor ckpc ckpr ckrc coak coba cobb cobe cobo coca coce cock coco cocp coep cok- coka coke coko coob cook coop copa cope copo copp copr cor- cora corb corc core cork coro corp corr cpaa cpac