a-a a-b a-t aaa aab aad aan aar aat aau ab- aba abb abd abn abr abt abu ad- ada adb add adn adr adt adu an- ana anb and ann anr ant anu ar- ara arb ard arn arr art aru at- ata atb atd atn atr att atu au- aua aub aud aun aur aut b-u baa bab bad ban bar bat bau bba bbb bbd bbn bbr bbt bbu bda bdb bdd bdr bdt bdu bna bnb bnd bnn bnr bnt bnu bra brb brd brn brr brt bru bta btb btd btn btr btt btu bua bub bud bun bur but buu daa dab dad dan dar dat dau dba dbb dbd dbn dbr dbt dbu dda ddb ddd ddn ddr ddt ddu dna dnb dnd dnn dnr dnt dra drb drd drn drr drt dru dta dtb dtd dtn dtr dtt dtu dua dub dud dun dur dut naa nab nad nan nar nat nau nba nbb nbd nbn nbr nbt nbu nda ndb ndd ndn ndr ndt ndu nna nnb nnn nnt nnu nra nrb nrd nrn nrr nrt nru nta ntb ntd ntn ntr ntt ntu nua nub nud nun nur nut nuu ra- raa rab rad ran rar rat rau rba rbb rbd rbn rbr rbt rbu rda rdb rdd rdn rdr rdt rdu rna rnb rnd rnn rnr rnt rnu rra rrb rrd rrn rrr rrt rru rta rtb rtd rtn rtr rtt rtu rua rub rud run rur rut ruu taa tab tad tan tar tat tau tba tbb tbd tbn tbr tbt tbu tda tdb tdd tdn tdr tdt tdu tna tnb tnd tnn tnr tnt tra trb trd trn trr trt tru tta ttb ttd ttn ttr ttt ttu tua tub tud tun tur tut tuu ua- uaa uab uad uan uar uat uau uba ubb ubn ubr ubt ubu uda udb udd udn udr udt udu un- una unb und unn unr unt unu ur- ura urb urd urn urr urt uru uta utb utd utn utr utt utu uua uun uur uut uuu