-er c-- ccc cce ccg ccn cco ccr ccs ce- cec cee ceg cen ceo cer ces cgc cge cgg cgn cgo cgr cgs cn- cnc cne cng cnn cno cnr cns co- coc coe cog con coo cor cos crc cre crg crn cro crr crs csc cse csg csn cso csr css ec- ecc ece ecg ecn eco ecr ecs eec eee eeg een eeo eer ees egc ege egg egn ego egr egs en- enc ene eng enn eno enr ens eo- eoc eoe eog eon eoo eor eos erc ere erg ern ero err ers es- esc ese esg esn eso esr ess gcc gce gcg gcn gco gcr gcs ge- gec gee geg gen geo ger ges ggc ggg ggn ggo ggr ggs gnc gne gnn gno gnr gns goc goe gog gon goo gor gos grc gre grg grn gro grr grs gsc gse gsg gsn gso gsr gss ncc nce ncg ncn nco ncr ncs ne- nec nee neg nen neo ner nes ngc nge ngg ngn ngo ngs nnc nne nng nnn nno nns no- noc noe nog non noo nor nos nrc nre nrg nrn nro nrr nrs nsc nse nsg nsn nso nsr nss oc- occ ocg ocn oco ocr ocs oec oee oeg oen oeo oer oes ogc oge ogg ogn ogo ogs on- onc one ong onn ono onr ons oo- ooc oog oon ooo oor oos or- orc ore org orn oro orr ors os- osc ose osg osn oso osr oss rcc rce rcg rcn rco rcr rcs re- rec ree reg ren reo rer res rgc rge rgg rgn rgo rgr rgs rnc rng rnn rno rnr rns roc roe rog ron roo ror ros rrc rrg rrn rrr rrs rsc rse rsg rsn rso rsr rss scc sce scg scn sco scr scs se- sec see seg sen seo ser ses sgc sge sgg sgn sgo sgr sgs snc sne sng snn sno snr sns soc soe sog son soo sor sos sr- src sre srg srn sro srr srs ss- ssc sse ssg ssn sso ssr sss