-th a-a a-b a-c a-t aaa aab aac aah aao aar aat aay ab- aba abb abc abh abo abr abt aby ac- aca acb acc ach aco acr act acy aha ahb ahc ahh aho ahr aht ahy aoa aob aoc aoh aoo aor aot ar- ara arb arc arh aro arr art ary at- ata atb atc ath ato atr att ay- aya ayc ayh ayo ayr ayt baa bab bac bah bao bar bat bay bba bbb bbc bbh bbo bbr bbt bby bca bcb bcc bch bco bcr bct bcy bha bhb bhc bhh bho bhr bht boa bob boc boh boo bor bot boy bra brb brh bro brr brt bry bta btb btc bth bto btr btt bty by- bya byc byh byo byr byt c-- caa cab cac cah cao car cat cay cba cbb cbc cbh cbo cbr cbt cby cca ccb ccc cch cco ccr cct ch- cha chb chc chh cho chr cht chy co- coa cob coc coh coo cor cot coy cra crb crc crh cro crr crt cry cta ctb ctc cth cto ctr ctt cty cya cyb cyc cyo cyr cyt haa hab hac hah hao har hat hay hba hbb hbc hbh hbo hbr hbt hby hca hcb hcc hch hco hcr hct hcy hha hhb hhc hhh hho hhr hht hhy hoa hob hoc hoh hoo hor hot hoy hr- hra hrb hrc hrh hro hrr hrt hta htb htc hth hto htr htt hty hy- hya hyb hyc hyh hyo hyr hyt hyy oaa oab oac oah oao oar oat ob- oba obb obc obh obo obr obt oby oc- oca ocb occ och oco ocr oct oha ohc ohh oho ohr oht oo- ooa oob ooc ooh ooo oor oot or- ora orb orc orh oro orr ort ory ot- ota otb otc oth oto otr ott oya oyo ra- raa rab rac rah rao rar rat ray rba rbb rbc rbh rbo rbr rbt rca rcb rcc rch rco rcr rct rh- rha rhb rhc rhh rho rhr rht roa rob roc roh roo ror rot roy rra rrb rrc rrh rrr rrt rta rtb rtc rto rtr rtt rty ry- rya ryc ryo ryr ryy taa tab tac tah tao tar tat tay tba tbb tbc tbh tbo tbr tbt tca tcb tcc tch tco tcr tct th- tha thb thc thh tho thr tht thy to- toa tob toc toh too tor tot toy tra trb trc trh tro trr trt try tta ttb ttc tth tto ttr ttt tty tya tyc tyo tyr tyt yaa yab yac yah yao yar yat yay ybc ybr yby yca ycc ych yco ycy yha yhc yht yob yoc yoo yor yot yoy yra yrc yro yrt yta ytc yth yto ytr ytt yyb yyc yyt yyy