a-a a-b a-t a-z aaa aab aan aar aat aau aaz ab- aba abb abn abr abt abu abz an- ana anb ann anr ant anu anz ar- ara arb arn arr art aru arz at- ata atb atn atr att atu atz au- aua aub aun aur aut auz az- aza azb azn azt azu azz b-u baa bab ban bar bat bau baz bba bbb bbn bbr bbt bbu bna bnb bnn bnr bnt bnu bnz bra brb brn brr brt bru brz bta btb btn btr btt btu btz bua bub bun bur but buu buz bza bzn bzr bzu bzz naa nab nan nar nat nau naz nba nbb nbn nbr nbt nbu nna nnb nnn nnt nnu nnz nra nrb nrn nrr nrt nru nrz nta ntb ntn ntr ntt ntu ntz nua nub nun nur nut nuu nzb nzz ra- raa rab ran rar rat rau raz rba rbb rbn rbr rbt rbu rna rnb rnn rnr rnt rnu rnz rra rrb rrn rrr rrt rru rta rtb rtn rtr rtt rtu rtz rua rub run rur rut ruu ruz rza rzb taa tab tan tar tat tau taz tba tbb tbn tbr tbt tbu tbz tna tnb tnn tnr tnt tnz tra trb trn trr trt tru trz tta ttb ttn ttr ttt ttu tua tub tun tur tut tuu tuz tza tzu ua- uaa uab uan uar uat uau uaz uba ubb ubn ubr ubt ubu un- una unb unn unr unt unu ur- ura urb urn urr urt uru urz uta utb utn utr utt utu utz uua uun uur uut uuu uza uzb uzu zaa zab zan zar zat zaz zbb zbr zbt znn zta ztr zub zun zur zut zuz zzr zzt zzz