a-a a-c aaa aac aae aag aak aas ac- aca acc ace acg ack acs aea aec aee aeg aek aes ag- aga agc age agg agk ags aka akc ake akg akk aks as- asa asc ase asg ask ass c-- caa cac cae cag cak cas cca ccc cce ccg cck ccs ce- cea cec cee ceg cek ces cga cgc cge cgg cgs cka ckc cks csa csc cse csg csk css eaa eac eae eag eak eas ec- eca ecc ece ecg eck ecs eea eec eee eeg eek ees ega egc ege egg egs eka ekc eke ekg eks es- esa esc ese esg esk ess gaa gac gae gag gak gas gca gcc gce gcg gck gcs ge- gea gec gee geg gek ges gga ggc ggg ggs gka gks gsa gsc gse gsg gsk gss ka- kaa kac kae kag kak kas kca kcc kce kcg kck kcs ke- kea kec kee keg kek kes kga kgc kgs kkc kke kkk kks ksa ksc kse ksg ksk kss saa sac sae sag sak sas sca scc sce scg sck scs se- sea sec see seg sek ses sga sgc sge sgg sgk sgs sk- ska skc ske skg skk sks ss- ssa ssc sse ssg ssk sss