-th a-a a-b a-c a-t aaa aab aac aah aak aao aar aat ab- aba abb abc abh abk abo abr abt ac- aca acb acc ach ack aco acr act aha ahb ahc ahh ahk aho ahr aht aka akb akc akh akk ako akr aoa aob aoc aoh aok aoo aor aot ar- ara arb arc arh ark aro arr art at- ata atb atc ath ato atr att baa bab bac bah bak bao bar bat bba bbb bbc bbh bbk bbo bbr bbt bca bcb bcc bch bck bco bcr bct bha bhb bhc bhh bhk bho bhr bht bka bkb bkc bkk bko bkr bkt boa bob boc boh bok boo bor bot bra brb brh brk bro brr brt bta btb btc bth btk bto btr btt c-- caa cab cac cah cak cao car cat cba cbb cbc cbh cbk cbo cbr cbt cca ccb ccc cch cck cco ccr cct ch- cha chb chc chh chk cho chr cht cka ckb ckc ckh cko ckt co- coa cob coc coh cok coo cor cot cra crb crc crh crk cro crr crt cta ctb ctc cth ctk cto ctr ctt haa hab hac hah hak hao har hat hba hbb hbc hbh hbk hbo hbr hbt hca hcb hcc hch hck hco hcr hct hha hhb hhc hhh hhk hho hhr hht hka hkb hkh hkk hko hkr hkt hoa hob hoc hoh hok hoo hor hot hr- hra hrb hrc hrh hrk hro hrr hrt hta htb htc hth htk hto htr htt k-t ka- kaa kab kac kah kak kao kar kat kba kbb kbc kbh kbk kbo kbr kca kcb kcc kch kck kcr kct kha khh khk kho khr kkb kkc kkh kkk kkr kkt koa kob koc koh kok koo kor kot kra krc krk kro krr krt kta ktb ktc kth ktk kto ktr ktt oaa oab oac oah oak oao oar oat ob- oba obb obc obh obk obo obr obt oc- oca ocb occ och ock oco ocr oct oha ohc ohh oho ohr oht oka okb okc okk oko okr oo- ooa oob ooc ooh ook ooo oor oot or- ora orb orc orh ork oro orr ort ot- ota otb otc oth otk oto otr ott ra- raa rab rac rah rak rao rar rat rba rbb rbc rbh rbk rbo rbr rbt rca rcb rcc rch rco rcr rct rh- rha rhb rhc rhh rho rhr rht rkb rkc rkk rko rkt roa rob roc roh rok roo ror rot rra rrb rrc rrh rrk rrr rrt rta rtb rtc rtk rto rtr rtt taa tab tac tah tak tao tar tat tba tbb tbc tbh tbk tbo tbr tbt tca tcb tcc tch tck tco tcr tct th- tha thb thc thh thk tho thr tht tka tkb tkc tkk tko tkr tkt to- toa tob toc toh tok too tor tot tra trb trc trh trk tro trr trt tta ttb ttc tth ttk tto ttr ttt