a-a a-b aaa aab aad aan aao aar aau ab- aba abb abd abn abo abr abu ad- ada adb add adn ado adr adu an- ana anb and ann ano anr anu aoa aob aod aon aoo aor aou ar- ara arb ard arn aro arr aru au- aua aub aud aun auo aur b-u baa bab bad ban bao bar bau bba bbb bbd bbn bbo bbr bbu bda bdb bdd bdo bdr bdu bna bnb bnd bnn bno bnr bnu boa bob bod bon boo bor bou bra brb brd brn bro brr bru bua bub bud bun buo bur buu daa dab dad dan dao dar dau dba dbb dbd dbn dbo dbr dbu dda ddb ddd ddn ddo ddr ddu dna dnb dnd dnn dno dnr doa dob dod don doo dor dou dra drb drd drn dro drr dru dua dub dud dun duo dur naa nab nad nan nao nar nau nba nbb nbd nbn nbo nbr nbu nda ndb ndd ndn ndo ndr ndu nna nnb nnn nno nnu no- noa nob nod non noo nor nou nra nrb nrd nrn nro nrr nru nua nub nud nun nuo nur nuu oaa oab oad oan oao oar oau ob- oba obb obd obn obo obr obu oda odb odd odn odo odr odu on- ona onb ond onn ono onr onu oo- ooa oob ood oon ooo oor or- ora orb ord orn oro orr oru ou- oua oud oun ouo our ra- raa rab rad ran rao rar rau rba rbb rbd rbn rbo rbr rbu rda rdb rdd rdn rdo rdr rdu rna rnb rnd rnn rno rnr rnu roa rob rod ron roo ror rou rra rrb rrd rrn rrr rru rua rub rud run ruo rur ruu ua- uaa uab uad uan uao uar uau uba ubb ubn ubo ubr ubu uda udb udd udn udo udr udu un- una unb und unn uno unr unu uoa uob uod uon uoo uor ur- ura urb urd urn uro urr uru uua uun uur uuu