-er a-a a-c a-t aaa aac aae aag aak aar aas aat ac- aca acc ace acg ack acr acs act aea aec aee aeg aek aer aes aet ag- aga agc age agg agk agr ags agt aka akc ake akg akk akr aks ar- ara arc are arg ark arr ars art as- asa asc ase asg ask asr ass ast at- ata atc ate atg atr ats att c-- caa cac cae cag cak car cas cat cca ccc cce ccg cck ccr ccs cct ce- cea cec cee ceg cek cer ces cet cga cgc cge cgg cgr cgs cgt cka ckc cks ckt cra crc cre crg crk crr crs crt csa csc cse csg csk csr css cst cta ctc cte ctg ctk ctr cts ctt eaa eac eae eag eak ear eas eat ec- eca ecc ece ecg eck ecr ecs ect eea eec eee eeg eek eer ees eet ega egc ege egg egr egs egt eka ekc eke ekg ekr eks ekt era erc ere erg erk err ers ert es- esa esc ese esg esk esr ess est eta etc ete etg etk etr ets ett gaa gac gae gag gak gar gas gat gca gcc gce gcg gck gcr gcs gct ge- gea gec gee geg gek ger ges get gga ggc ggg ggr ggs ggt gka gks gkt gra grc gre grg grk grr grs grt gsa gsc gse gsg gsk gsr gss gst gta gtc gte gtg gtk gtr gts gtt k-t ka- kaa kac kae kag kak kar kas kat kca kcc kce kcg kck kcr kcs kct ke- kea kec kee keg kek ker kes ket kga kgc kgs kkc kke kkk kkr kks kkt kra krc krg krk krr krs krt ksa ksc kse ksg ksk ksr kss kst kta ktc kte ktg ktk ktr kts ktt ra- raa rac rae rag rak rar ras rat rca rcc rce rcg rcr rcs rct re- rea rec ree reg rek rer res ret rga rgc rge rgg rgk rgr rgs rgt rkc rke rkg rkk rks rkt rra rrc rrg rrk rrr rrs rrt rsa rsc rse rsg rsk rsr rss rst rta rtc rte rtg rtk rtr rts rtt saa sac sae sag sak sar sas sat sca scc sce scg sck scr scs sct se- sea sec see seg sek ser ses set sga sgc sge sgg sgk sgr sgs sgt sk- ska skc ske skg skk skr sks skt sr- sra src sre srg srk srr srs srt ss- ssa ssc sse ssg ssk ssr sss sst sta stc ste stg stk str sts stt taa tac tae tag tak tar tas tat tca tcc tce tcg tck tcr tcs tct te- tea tec tee teg tek ter tes tet tga tgc tge tgg tgk tgr tgs tgt tka tkc tke tkg tkk tkr tks tkt tra trc tre trg trk trr trs trt tsa tsc tse tsg tsk tsr tss tst tta ttc tte ttg ttk ttr tts ttt