a-a a-b a-i a-z aaa aab aai aak aao aaz ab- aba abb abi abk abo abz ai- aia aib aii aik aio aiz aka akb aki akk ako aoa aob aoi aok aoo az- aza azb azi azo azz baa bab bai bak bao baz bba bbb bbi bbk bbo bi- bia bib bii bik bio biz bka bkb bkk bko boa bob boi bok boo boz bza bzo bzz ia- iaa iab iai iao iaz iba ibb ibi ibk ibo ibz iia iib iii iio ika ikb iki ikk iko io- ioa iob ioi ioo iza izi izo izz k-z ka- kaa kab kai kak kao kaz kba kbb kbi kbk kbo kbz kia kib kii kik kio kiz kkb kki kkk koa kob koi kok koo koz kzo o-i oaa oab oai oak oao ob- oba obb obi obk obo oia oib oii oik oio oiz oka okb oki okk oko oo- ooa oob ooi ook ooo oza ozo ozz zaa zab zai zak zao zaz zbb zia zib zik zio ziz zka zo- zoa zob zoi zok zoo zzz