ceno[5], noce[5], ocen[5], open[5], peon[5], poen[5],
cep[5], cen[4], cne[4], noc[4], nep[4], pen[4], eon[3], one[3],
ce[3], co[3], pe[3], op[3], po[3], ee[2], en[2], eo[2], no[2], on[2],