-er a-a a-c aaa aac aae aag aao aap aar aas ac- aca acc ace acg aco acp acr acs aea aec aee aeg aeo aep aer aes ag- aga agc age agg ago agp agr ags aoa aoc aoe aog aoo aop aor aos ap- apa apc ape apg apo app apr aps ar- ara arc are arg aro arp arr ars as- asa asc ase asg aso asp asr ass c-- caa cac cae cag cao cap car cas cca ccc cce ccg cco ccp ccr ccs ce- cea cec cee ceg ceo cep cer ces cga cgc cge cgg cgo cgp cgr cgs co- coa coc coe cog coo cop cor cos cpa cpc cpe cpg cpo cpp cpr cps cra crc cre crg cro crp crr crs csa csc cse csg cso csp csr css eaa eac eae eag eao eap ear eas ec- eca ecc ece ecg eco ecr ecs eea eec eee eeg eeo eep eer ees ega egc ege egg ego egp egr egs eo- eoa eoc eoe eog eoo eop eor eos ep- epa epc epe epg epo epp epr eps era erc ere erg ero erp err ers es- esa esc ese esg eso esp esr ess g-p gaa gac gae gag gao gap gar gas gca gcc gce gcg gco gcp gcr gcs ge- gea gec gee geg geo gep ger ges gga ggc ggg ggo ggp ggr ggs goa goc goe gog goo gop gor gos gpa gpc gpe gpg gpo gpp gpr gps gra grc gre grg gro grp grr grs gsa gsc gse gsg gso gsp gsr gss oaa oac oae oag oao oap oar oas oc- oca occ ocg oco ocp ocr ocs oea oec oee oeg oeo oep oer oes oga ogc oge ogg ogo ogp ogs oo- ooa ooc oog ooo oop oor oos op- opa opc ope opg opo opp opr ops or- ora orc ore org oro orp orr ors os- osa osc ose osg oso osp osr oss p-p paa pac pae pag pao pap par pas pca pcc pce pcg pco pcp pcr pcs pea pec pee peg peo pep per pes pga pgc pge pgg pgo pgp pgr pgs poa poc poe pog poo pop por pos ppa ppc ppe ppg ppo ppp ppr pps pra prc pre prg pro prp prr prs ps- psa psc pse psg pso psp psr pss ra- raa rac rae rag rao rap rar ras rca rcc rce rcg rco rcp rcr rcs re- rea rec ree reg reo rep rer res rga rgc rge rgg rgo rgp rgr rgs roa roc roe rog roo rop ror ros rpa rpc rpe rpg rpo rpp rpr rps rra rrc rrg rrp rrr rrs rsa rsc rse rsg rso rsp rsr rss saa sac sae sag sao sap sar sas sca scc sce scg sco scp scr scs se- sea sec see seg seo sep ser ses sga sgc sge sgg sgo sgp sgr sgs soa soc soe sog soo sop sor sos spa spc spe spg spo spp spr sps sr- sra src sre srg sro srp srr srs ss- ssa ssc sse ssg sso ssp ssr sss