a-a a-c aaa aac aah aan aao aax ac- aca acc ach acn aco acx aha ahc ahh ahn aho ahx an- ana anc anh ann ano anx aoa aoc aoh aon aoo aox ax- axa axh axn axo axx c-- caa cac cah can cao cax cca ccc cch ccn cco ccx ch- cha chc chh chn cho chx cn- cna cnc cnh cnn cno cnx co- coa coc coh con coo cox cxc cxh cxo cxx haa hac hah han hao hax hca hcc hch hcn hco hha hhc hhh hhn hho hna hnc hnh hnn hno hoa hoc hoh hon hoo hox hxc naa nac nah nan nao nax nca ncc nch ncn nco ncx nha nhc nhh nhn nna nnc nnh nnn nno no- noa noc noh non noo nox nxc oaa oac oah oan oao oax oc- oca occ och ocn oco ocx oha ohc ohh ohn oho on- ona onc onh onn ono onx oo- ooa ooc ooh oon ooo oox ox- oxa oxc oxn oxo oxx xaa xac xan xch xcx xna xnc xno xoa xoc xon xoo xox xxo xxx