-er a-a a-c aaa aac aae aag aan aar ac- aca acc ace acg acn acr aea aec aee aeg aen aer ag- aga agc age agg agn agr an- ana anc ane ang ann anr ar- ara arc are arg arn arr c-- caa cac cae cag can car cca ccc cce ccg ccn ccr ce- cea cec cee ceg cen cer cga cgc cge cgg cgn cgr cn- cna cnc cne cng cnn cnr cra crc cre crg crn crr eaa eac eae eag ean ear ec- eca ecc ece ecg ecn ecr eea eec eee eeg een eer ega egc ege egg egn egr en- ena enc ene eng enn enr era erc ere erg ern err gaa gac gae gag gan gar gca gcc gce gcg gcn gcr ge- gea gec gee geg gen ger gga ggc ggg ggn ggr gna gnc gne gnn gnr gra grc gre grg grn grr naa nac nae nag nan nar nca ncc nce ncg ncn ncr ne- nea nec nee neg nen ner nga ngc nge ngg ngn nna nnc nne nng nnn nra nrc nre nrg nrn nrr ra- raa rac rae rag ran rar rca rcc rce rcg rcn rcr re- rea rec ree reg ren rer rga rgc rge rgg rgn rgr rna rnc rng rnn rnr rra rrc rrg rrn rrr