a-a a-b aaa aab aad aan aao aax aay ab- aba abb abd abn abo abx aby ad- ada adb add adn ado adx ady an- ana anb and ann ano anx any aoa aob aod aon aoo aox ax- axa axn axo axx ay- aya ayd ayn ayo ayx baa bab bad ban bao bax bay bba bbb bbd bbn bbo bbx bby bda bdb bdd bdo bdx bdy bna bnb bnd bnn bno bnx boa bob bod bon boo box boy bxb bxd bxn bxo bxx by- bya byd byn byo daa dab dad dan dao dax day dba dbb dbd dbn dbo dbx dby dda ddb ddd ddn ddo ddx ddy dna dnb dnd dnn dno dny doa dob dod don doo dox doy dxd dxn dxo dxx dy- dya dyb dyd dyn dyo dyy naa nab nad nan nao nax nay nba nbb nbd nbn nbo nbx nda ndb ndd ndn ndo ndy nna nnb nnn nno no- noa nob nod non noo nox noy nxd nya nyd nyn nyo nyx nyy oaa oab oad oan oao oax ob- oba obb obd obn obo obx oby oda odb odd odn odo on- ona onb ond onn ono onx ony oo- ooa oob ood oon ooo oox ox- oxa oxb oxn oxo oxx oxy oya oyd oyo xaa xad xan xbx xda xdb xna xno xoa xod xon xoo xox xxo xxx xxy xyy yaa yab yad yan yao yax yay yby yda ydn ydo ydy yna ynd ynn yny yob yod yon yoo yox yoy yxa yxy yyb yyy