a-a a-b a-t a-z aaa aab aan aao aat aaz ab- aba abb abn abo abt abz an- ana anb ann ano ant anz aoa aob aon aoo aot at- ata atb atn ato att atz az- aza azb azn azo azt azz baa bab ban bao bat baz bba bbb bbn bbo bbt bna bnb bnn bno bnt bnz boa bob bon boo bot boz bta btb btn bto btt btz bza bzn bzo bzz naa nab nan nao nat naz nba nbb nbn nbo nbt nna nnb nnn nno nnt nnz no- noa nob non noo not noz nta ntb ntn nto ntt ntz nzb nzo nzz oaa oab oan oao oat ob- oba obb obn obo obt on- ona onb onn ono ont oo- ooa oob oon ooo oot ot- ota otb otn oto ott otz oza ozo ozt ozz taa tab tan tao tat taz tba tbb tbn tbo tbt tbz tna tnb tnn tno tnt tnz to- toa tob ton too tot toz tta ttb ttn tto ttt tza zaa zab zan zao zat zaz zbb zbt znn zno zo- zoa zob zon zoo zot zta zzt zzz