a-a a-c aaa aac aag aar aau aax ac- aca acc acg acr acu acx ag- aga agc agg agr agu agx ar- ara arc arg arr aru arx au- aua auc aug aur aux ax- axa axr axx c-- caa cac cag car cau cax cca ccc ccg ccr ccu ccx cga cgc cgg cgr cgu cra crc crg crr cru crx cua cuc cug cur cuu cxc cxr cxx gaa gac gag gar gau gca gcc gcg gcr gcu gga ggc ggg ggr ggu gra grc grg grr gru grx gu- gua guc gug gur guu gxa ra- raa rac rag rar rau rax rca rcc rcg rcr rcu rcx rga rgc rgg rgr rgx rra rrc rrg rrr rru rua ruc rug rur ruu rux rxr ua- uaa uac uag uar uau uca ucc ucg ucr ucu uga ugc ugg ugr ugu ugx ur- ura urc urg urr uru urx uua uuc uug uur uuu uxc uxr uxu xaa xac xag xar xau xcr xcx xrc xrx xxx