a-a a-b a-t aaa aab aak aao aat aav ab- aba abb abk abo abt abv aka akb akk ako akv aoa aob aok aoo aot aov at- ata atb ato att atv av- ava avb avk avo avt baa bab bak bao bat bav bba bbb bbk bbo bbt bka bkb bkk bko bkt bkv boa bob bok boo bot bov bta btb btk bto btt btv bva bvb bvk bvo bvt bvv k-t ka- kaa kab kak kao kat kav kba kbb kbk kbo kkb kkk kkt kkv koa kob kok koo kot kta ktb ktk kto ktt ktv kva kvb kvk kvo kvv oaa oab oak oao oat oav ob- oba obb obk obo obt obv oka okb okk oko oo- ooa oob ook ooo oot oov ot- ota otb otk oto ott otv ov- ova ovb ovo ovv taa tab tak tao tat tav tba tbb tbk tbo tbt tbv tka tkb tkk tko tkt to- toa tob tok too tot tov tta ttb ttk tto ttt ttv tva tvb tvk tvo tvt v-a vaa vab vak vao vat vav vba vbk vbo vbv vka vkb vkt voa vob vok voo vot vov vta vtb vtk vto vtt vtv vva vvb vvo vvt vvv