a-a a-b a-t aaa aab aan aao aar aat aau ab- aba abb abn abo abr abt abu an- ana anb ann ano anr ant anu aoa aob aon aoo aor aot aou ar- ara arb arn aro arr art aru at- ata atb atn ato atr att atu au- aua aub aun auo aur aut b-u baa bab ban bao bar bat bau bba bbb bbn bbo bbr bbt bbu bna bnb bnn bno bnr bnt bnu boa bob bon boo bor bot bou bra brb brn bro brr brt bru bta btb btn bto btr btt btu bua bub bun buo bur but buu naa nab nan nao nar nat nau nba nbb nbn nbo nbr nbt nbu nna nnb nnn nno nnt nnu no- noa nob non noo nor not nou nra nrb nrn nro nrr nrt nru nta ntb ntn nto ntr ntt ntu nua nub nun nuo nur nut nuu oaa oab oan oao oar oat oau ob- oba obb obn obo obr obt obu on- ona onb onn ono onr ont onu oo- ooa oob oon ooo oor oot or- ora orb orn oro orr ort oru ot- ota otb otn oto otr ott otu ou- oua oun ouo our out ra- raa rab ran rao rar rat rau rba rbb rbn rbo rbr rbt rbu rna rnb rnn rno rnr rnt rnu roa rob ron roo ror rot rou rra rrb rrn rrr rrt rru rta rtb rtn rto rtr rtt rtu rua rub run ruo rur rut ruu taa tab tan tao tar tat tau tba tbb tbn tbo tbr tbt tbu tna tnb tnn tno tnr tnt to- toa tob ton too tor tot tou tra trb trn tro trr trt tru tta ttb ttn tto ttr ttt ttu tua tub tun tuo tur tut tuu ua- uaa uab uan uao uar uat uau uba ubb ubn ubo ubr ubt ubu un- una unb unn uno unr unt unu uoa uob uon uoo uor uot ur- ura urb urn uro urr urt uru uta utb utn uto utr utt utu uua uun uur uut uuu