-er c-- ccc cce ccg ccn cco ccr ce- cec cee ceg cen ceo cer cgc cge cgg cgn cgo cgr cn- cnc cne cng cnn cno cnr co- coc coe cog con coo cor crc cre crg crn cro crr ec- ecc ece ecg ecn eco ecr eec eee eeg een eeo eer egc ege egg egn ego egr en- enc ene eng enn eno enr eo- eoc eoe eog eon eoo eor erc ere erg ern ero err gcc gce gcg gcn gco gcr ge- gec gee geg gen geo ger ggc ggg ggn ggo ggr gnc gne gnn gno gnr goc goe gog gon goo gor grc gre grg grn gro grr ncc nce ncg ncn nco ncr ne- nec nee neg nen neo ner ngc nge ngg ngn ngo nnc nne nng nnn nno no- noc noe nog non noo nor nrc nre nrg nrn nro nrr oc- occ ocg ocn oco ocr oec oee oeg oen oeo oer ogc oge ogg ogn ogo on- onc one ong onn ono onr oo- ooc oog oon ooo oor or- orc ore org orn oro orr rcc rce rcg rcn rco rcr re- rec ree reg ren reo rer rgc rge rgg rgn rgo rgr rnc rng rnn rno rnr roc roe rog ron roo ror rrc rrg rrn rrr