a-a a-b aaa aab aad aak aan aao aay ab- aba abb abd abk abn abo aby ad- ada adb add adk adn ado ady aka akb akd akk akn ako an- ana anb and ank ann ano any aoa aob aod aok aon aoo ay- aya ayd ayk ayn ayo baa bab bad bak ban bao bay bba bbb bbd bbk bbn bbo bby bda bdb bdd bdk bdo bdy bka bkb bkk bkn bko bna bnb bnd bnk bnn bno boa bob bod bok bon boo boy by- bya byd byk byn byo daa dab dad dak dan dao day dba dbb dbd dbk dbn dbo dby dda ddb ddd ddk ddn ddo ddy dka dkb dkk dko dna dnb dnd dnk dnn dno dny doa dob dod dok don doo doy dy- dya dyb dyd dyk dyn dyo dyy ka- kaa kab kad kak kan kao kay kba kbb kbd kbk kbn kbo kda kdb kdk kdo kdy kkb kkk kkn kky kn- kna knd knk knn kno koa kob kod kok kon koo koy kya kyd kyn kyo naa nab nad nak nan nao nay nba nbb nbd nbk nbn nbo nda ndb ndd ndk ndn ndo ndy nka nkk nkn nko nky nna nnb nnk nnn nno no- noa nob nod nok non noo noy nya nyd nyk nyn nyo nyy oaa oab oad oak oan oao ob- oba obb obd obk obn obo oby oda odb odd odn odo oka okb okd okk oko on- ona onb ond onk onn ono ony oo- ooa oob ood ook oon ooo oya oyd oyo yaa yab yad yak yan yao yay yby yda ydn ydo ydy yka ykk ykn yna ynd ynk ynn yny yob yod yok yon yoo yoy yyb yyy