a-a a-b a-z aaa aab aak aan aaz ab- aba abb abk abn abz aka akb akk akn an- ana anb ank ann anz az- aza azb azn azz baa bab bak ban baz bba bbb bbk bbn bka bkb bkk bkn bna bnb bnk bnn bnz bza bzn bzz k-z ka- kaa kab kak kan kaz kba kbb kbk kbn kbz kkb kkk kkn kn- kna knk knn naa nab nak nan naz nba nbb nbk nbn nka nkk nkn nna nnb nnk nnn nnz nzb nzz zaa zab zak zan zaz zbb zka znn zzz