-er a-a a-c aaa aac aae aag aam aao aar ac- aca acc ace acg acm aco acr aea aec aee aeg aem aeo aer ag- aga agc age agg agm ago agr ama amc ame amg amm amo amr aoa aoc aoe aog aom aoo aor ar- ara arc are arg arm aro arr c-- caa cac cae cag cam cao car cca ccc cce ccg ccm cco ccr ce- cea cec cee ceg cem ceo cer cga cgc cge cgg cgm cgo cgr cma cmc cme cmg cmm cmo cmr co- coa coc coe cog com coo cor cra crc cre crg crm cro crr eaa eac eae eag eam eao ear ec- eca ecc ece ecg ecm eco ecr eea eec eee eeg eem eeo eer ega egc ege egg egm ego egr em- ema emc eme emg emm emo emr eo- eoa eoc eoe eog eom eoo eor era erc ere erg erm ero err gaa gac gae gag gam gao gar gca gcc gce gcg gcm gco gcr ge- gea gec gee geg gem geo ger gga ggc ggg ggm ggo ggr gma gmc gme gmg gmm gmo gmr goa goc goe gog gom goo gor gra grc gre grg grm gro grr m-o m-r maa mac mae mag mam mao mar mc- mca mcc mce mcg mcm mco mcr mea mec mee meg mem meo mer mga mgc mge mgm mgo mgr mma mmc mme mmg mmm mmo mmr moa moc moe mog mom moo mor mra mrc mre mrg mrm mro mrr oaa oac oae oag oam oao oar oc- oca occ ocg ocm oco ocr oea oec oee oeg oem oeo oer oga ogc oge ogg ogo om- oma omc ome omg omm omo omr oo- ooa ooc oog oom ooo oor or- ora orc ore org orm oro orr ra- raa rac rae rag ram rao rar rca rcc rce rcg rcm rco rcr re- rea rec ree reg rem reo rer rga rgc rge rgg rgo rgr rma rmc rme rmg rmm rmo rmr roa roc roe rog rom roo ror rra rrc rrg rrm rrr