c-one c-p-c c-pop ccccc ceco- cecon ceene cence cenex ceno- cenon cenpn cenpo ceoce cepno ceppo cnnnn co-co co-np co-op cocc- cocce cocco coceo cocon coen- coepe conco conex conne cono- conon conop cooee coone coope copce copec copen coppe coppo coxen coxon e-one eccen econo eeeee eence eepee eneco enone enope enpo epeen epene epone excon excop execx exene exopc exxon n-p-n necco neece nenno neope neppe nexen nexoe nexon nnooo no-no no-op nonce nonne nonno nonop nonpc noone nopep noppe noxon oceno ocoee oeco- oeno- oenoe oeppo oncee onco- one-x onene oneno oneon oneop onne- onnen onone onoon onpop onxeo ooooo opcon openx opepe opone oppon p-n-p p-o-x pecco pecon peece peene pence penco pene- penex penne penon peone pepco pepee pepon peppe pexec pneo- po-on po-po pocno pocop ponce ponne poope poopo popco popex popon popop poppe poppo poxon pppox x-one xeno- xenon xepon xexex xonox xoxox