-er a-a a-c aaa aac aae aag aan aao aar ac- aca acc ace acg acn aco acr aea aec aee aeg aen aeo aer ag- aga agc age agg agn ago agr an- ana anc ane ang ann ano anr aoa aoc aoe aog aon aoo aor ar- ara arc are arg arn aro arr c-- caa cac cae cag can cao car cca ccc cce ccg ccn cco ccr ce- cea cec cee ceg cen ceo cer cga cgc cge cgg cgn cgo cgr cn- cna cnc cne cng cnn cno cnr co- coa coc coe cog con coo cor cra crc cre crg crn cro crr eaa eac eae eag ean eao ear ec- eca ecc ece ecg ecn eco ecr eea eec eee eeg een eeo eer ega egc ege egg egn ego egr en- ena enc ene eng enn eno enr eo- eoa eoc eoe eog eon eoo eor era erc ere erg ern ero err gaa gac gae gag gan gao gar gca gcc gce gcg gcn gco gcr ge- gea gec gee geg gen geo ger gga ggc ggg ggn ggo ggr gna gnc gne gnn gno gnr goa goc goe gog gon goo gor gra grc gre grg grn gro grr naa nac nae nag nan nao nar nca ncc nce ncg ncn nco ncr ne- nea nec nee neg nen neo ner nga ngc nge ngg ngn ngo nna nnc nne nng nnn nno no- noa noc noe nog non noo nor nra nrc nre nrg nrn nro nrr oaa oac oae oag oan oao oar oc- oca occ ocg ocn oco ocr oea oec oee oeg oen oeo oer oga ogc oge ogg ogn ogo on- ona onc one ong onn ono onr oo- ooa ooc oog oon ooo oor or- ora orc ore org orn oro orr ra- raa rac rae rag ran rao rar rca rcc rce rcg rcn rco rcr re- rea rec ree reg ren reo rer rga rgc rge rgg rgn rgo rgr rna rnc rng rnn rno rnr roa roc roe rog ron roo ror rra rrc rrg rrn rrr