a-a a-b aaa aab aad aae aah aan ab- aba abb abd abe abh abn ad- ada adb add ade adh adn aea aeb aed aee aeh aen aha ahb ahd ahe ahh ahn an- ana anb and ane anh ann baa bab bad bae bah ban bba bbb bbd bbe bbh bbn bda bdb bdd bde bdh be- bea beb bed bee beh ben bha bhb bhd bhe bhh bna bnb bnd bne bnn daa dab dad dae dah dan dba dbb dbd dbe dbh dbn dda ddb ddd dde ddh ddn de- dea deb ded dee deh den dh- dha dhb dhd dhe dhh dna dnb dnd dne dnh dnn eaa eab ead eae eah ean eba ebb ebd ebe ebh ebn ed- eda edb edd ede edh edn eea eeb eed eee een eha ehb ehd ehe ehh ehn en- ena enb end ene enh enn haa hab had hae hah han hba hbb hbd hbe hbh hbn hda hdb hdd hde hdh hdn he- hea heb hed hee heh hen hha hhb hhd hhe hhh hhn hna hnb hnd hne hnh hnn naa nab nad nae nah nan nba nbb nbd nbe nbn nda ndb ndd nde ndh ndn ne- nea neb ned nee neh nen nha nhb nhd nhe nhh nhn nna nnb nne nnh nnn