a-a a-c aaa aac aag aak aao aar ac- aca acc acg ack aco acr ag- aga agc agg agk ago agr aka akc akg akk ako akr aoa aoc aog aok aoo aor ar- ara arc arg ark aro arr c-- caa cac cag cak cao car cca ccc ccg cck cco ccr cga cgc cgg cgo cgr cka ckc cko co- coa coc cog cok coo cor cra crc crg crk cro crr gaa gac gag gak gao gar gca gcc gcg gck gco gcr gga ggc ggg ggo ggr gka gko goa goc gog gok goo gor gra grc grg grk gro grr ka- kaa kac kag kak kao kar kca kcc kcg kck kcr kga kgc kgo kkc kkk kkr koa koc kog kok koo kor kra krc krg krk kro krr oaa oac oag oak oao oar oc- oca occ ocg ock oco ocr oga ogc ogg ogo oka okc okg okk oko okr oo- ooa ooc oog ook ooo oor or- ora orc org ork oro orr ra- raa rac rag rak rao rar rca rcc rcg rco rcr rga rgc rgg rgk rgo rgr rkc rkg rkk rko roa roc rog rok roo ror rra rrc rrg rrk rrr