a-a a-c a-t a-z aaa aac aao aar aat aaz ac- aca acc aco acr act acz aoa aoc aoo aor aot ar- ara arc aro arr art arz at- ata atc ato atr att atz az- aza azo azt azz c-- caa cac cao car cat caz cca ccc cco ccr cct ccz co- coa coc coo cor cot coz cra crc cro crr crt crz cta ctc cto ctr ctt ctz cz- czc czo czt oaa oac oao oar oat oc- oca occ oco ocr oct ocz oo- ooa ooc ooo oor oot or- ora orc oro orr ort orz ot- ota otc oto otr ott otz oza ozo ozt ozz ra- raa rac rao rar rat raz rca rcc rco rcr rct roa roc roo ror rot roz rra rrc rrr rrt rta rtc rto rtr rtt rtz rza rzo taa tac tao tar tat taz tca tcc tco tcr tct to- toa toc too tor tot toz tra trc tro trr trt trz tta ttc tto ttr ttt tza zaa zac zao zar zat zaz zco zo- zoa zoc zoo zor zot zro zta ztr zzr zzt zzz