a-a a-b aaa aab aam aan aao aar aau ab- aba abb abm abn abo abr abu ama amb amm amn amo amr amu an- ana anb anm ann ano anr anu aoa aob aom aon aoo aor aou ar- ara arb arm arn aro arr aru au- aua aub aum aun auo aur b-u baa bab bam ban bao bar bau bba bbb bbm bbn bbo bbr bbu bma bmb bmm bmn bmo bmr bmu bna bnb bnn bno bnr bnu boa bob bom bon boo bor bou bra brb brm brn bro brr bru bua bub bum bun buo bur buu m-o m-r maa mab mam man mao mar mau mba mbb mbm mbo mbr mbu mma mmb mmm mmn mmo mmr mmu mna mnb mnm mnn mno mnr mnu moa mob mom mon moo mor mou mra mrb mrm mrn mro mrr mru mua mub mum mun mur muu naa nab nam nan nao nar nau nba nbb nbm nbn nbo nbr nbu nma nmb nmm nmn nmo nmr nmu nna nnb nnm nnn nno nnu no- noa nob nom non noo nor nou nra nrb nrm nrn nro nrr nru nua nub num nun nuo nur nuu oaa oab oam oan oao oar oau ob- oba obb obm obn obo obr obu om- oma omb omm omn omo omr omu on- ona onb onn ono onr onu oo- ooa oob oom oon ooo oor or- ora orb orm orn oro orr oru ou- oua oum oun ouo our ra- raa rab ram ran rao rar rau rba rbb rbm rbn rbo rbr rbu rma rmb rmm rmn rmo rmr rna rnb rnm rnn rno rnr rnu roa rob rom ron roo ror rou rra rrb rrm rrn rrr rru rua rub rum run ruo rur ruu ua- uaa uab uam uan uao uar uau uba ubb ubn ubo ubr ubu um- uma umb umm umn umo umr umu un- una unb unm unn uno unr unu uoa uob uom uon uoo uor ur- ura urb urm urn uro urr uru uua uum uun uur uuu