a-a a-b a-t aaa aab aam aan aao aat ab- aba abb abm abn abo abt ama amb amm amn amo amt an- ana anb anm ann ano ant aoa aob aom aon aoo aot at- ata atb atm atn ato att baa bab bam ban bao bat bba bbb bbm bbn bbo bbt bma bmb bmm bmn bmo bmt bna bnb bnn bno bnt boa bob bom bon boo bot bta btb btm btn bto btt m-o maa mab mam man mao mat mba mbb mbm mbo mbt mma mmb mmm mmn mmo mmt mna mnb mnm mnn mno mnt moa mob mom mon moo mot mta mtb mtm mtn mto mtt naa nab nam nan nao nat nba nbb nbm nbn nbo nbt nma nmb nmm nmn nmo nmt nna nnb nnm nnn nno nnt no- noa nob nom non noo not nta ntb ntm ntn nto ntt oaa oab oam oan oao oat ob- oba obb obm obn obo obt om- oma omb omm omn omo omt on- ona onb onn ono ont oo- ooa oob oom oon ooo oot ot- ota otb otm otn oto ott taa tab tam tan tao tat tba tbb tbm tbn tbo tbt tma tmb tmm tmn tmo tmt tna tnb tnm tnn tno tnt to- toa tob tom ton too tot tta ttb ttm ttn tto ttt