-er -ey c-- ccc cce ccn ccr ccx ce- cec cee cen cer cex cey cn- cnc cne cnn cnr cnx cny crc cre crn crr crx cry cxc cxr cxx cyc cye cyn cyr ec- ecc ece ecn ecr ecx eec eee een eer eex eey en- enc ene enn enr eny erc ere ern err ery ex- exc exe exr exx exy eyc eye eyn eyr ncc nce ncn ncr ncx ne- nec nee nen ner nex ney nnc nne nnn nrc nre nrn nrr nrx nry nxc nyc nye nyn nyx nyy rcc rce rcn rcr rcx re- rec ree ren rer rex rey rnc rnn rnr rny rrc rrn rrr rxr ry- ryc rye ryn ryr ryy xcr xcx xee xen xer xex xnc xrc xrx xry xxx xxy xyr xyy ycc yce ycy yec yee yen yer yex yey yne ynn yny yrc yre yrn yxe yxy yyc yye yyy