a-a a-b a-c aaa aab aac aad aah aak aan ab- aba abb abc abd abh abk abn ac- aca acb acc acd ach ack acn ad- ada adb adc add adh adk adn aha ahb ahc ahd ahh ahk ahn aka akb akc akd akh akk akn an- ana anb anc and anh ank ann baa bab bac bad bah bak ban bba bbb bbc bbd bbh bbk bbn bca bcb bcc bcd bch bck bcn bda bdb bdc bdd bdh bdk bha bhb bhc bhd bhh bhk bka bkb bkc bkk bkn bna bnb bnc bnd bnk bnn c-- caa cab cac cad cah cak can cba cbb cbc cbd cbh cbk cbn cca ccb ccc ccd cch cck ccn cda cdb cdc cdd cdh cdk cdn ch- cha chb chc chd chh chk chn cka ckb ckc ckd ckh cn- cna cnb cnc cnd cnh cnn daa dab dac dad dah dak dan dba dbb dbc dbd dbh dbk dbn dca dcb dcc dcd dck dcn dda ddb ddc ddd ddh ddk ddn dh- dha dhb dhc dhd dhh dhk dka dkb dkc dkk dna dnb dnc dnd dnh dnk dnn haa hab hac had hah hak han hba hbb hbc hbd hbh hbk hbn hca hcb hcc hcd hch hck hcn hda hdb hdc hdd hdh hdk hdn hha hhb hhc hhd hhh hhk hhn hka hkb hkd hkh hkk hkn hna hnb hnc hnd hnh hnk hnn ka- kaa kab kac kad kah kak kan kba kbb kbc kbd kbh kbk kbn kca kcb kcc kcd kch kck kcn kda kdb kdc kdh kdk kha khh khk khn kkb kkc kkh kkk kkn kn- kna knc knd knk knn naa nab nac nad nah nak nan nba nbb nbc nbd nbk nbn nca ncb ncc ncd nch nck ncn nda ndb ndc ndd ndh ndk ndn nha nhb nhc nhd nhh nhk nhn nka nkc nkk nkn nna nnb nnc nnh nnk nnn