a-a a-b a-t aaa aab aak aam aao aar aat ab- aba abb abk abm abo abr abt aka akb akk akm ako akr ama amb amk amm amo amr amt aoa aob aok aom aoo aor aot ar- ara arb ark arm aro arr art at- ata atb atm ato atr att baa bab bak bam bao bar bat bba bbb bbk bbm bbo bbr bbt bka bkb bkk bkm bko bkr bkt bma bmb bmk bmm bmo bmr bmt boa bob bok bom boo bor bot bra brb brk brm bro brr brt bta btb btk btm bto btr btt k-t ka- kaa kab kak kam kao kar kat kba kbb kbk kbm kbo kbr kkb kkk kkm kkr kkt kma kmb kmk kmm kmo kmt koa kob kok kom koo kor kot kra krk kro krr krt kta ktb ktk ktm kto ktr ktt m-o m-r maa mab mak mam mao mar mat mba mbb mbk mbm mbo mbr mbt mka mkb mkk mkm mko mkr mkt mma mmb mmk mmm mmo mmr mmt moa mob mok mom moo mor mot mra mrb mrk mrm mro mrr mrt mta mtb mtk mtm mto mtr mtt oaa oab oak oam oao oar oat ob- oba obb obk obm obo obr obt oka okb okk oko okr om- oma omb omm omo omr omt oo- ooa oob ook oom ooo oor oot or- ora orb ork orm oro orr ort ot- ota otb otk otm oto otr ott ra- raa rab rak ram rao rar rat rba rbb rbk rbm rbo rbr rbt rkb rkk rkm rko rkt rma rmb rmm rmo rmr rmt roa rob rok rom roo ror rot rra rrb rrk rrm rrr rrt rta rtb rtk rtm rto rtr rtt taa tab tak tam tao tar tat tba tbb tbk tbm tbo tbr tbt tka tkb tkk tkm tko tkr tkt tma tmb tmk tmm tmo tmr tmt to- toa tob tok tom too tor tot tra trb trk trm tro trr trt tta ttb ttk ttm tto ttr ttt