a-a a-b a-c aaa aab aac aah aan aay ab- aba abb abc abh abn aby ac- aca acb acc ach acn acy aha ahb ahc ahh ahn ahy an- ana anb anc anh ann any ay- aya ayc ayh ayn baa bab bac bah ban bay bba bbb bbc bbh bbn bby bca bcb bcc bch bcn bcy bha bhb bhc bhh bna bnb bnc bnn by- bya byc byh byn c-- caa cab cac cah can cay cba cbb cbc cbh cbn cby cca ccb ccc cch ccn ch- cha chb chc chh chn chy cn- cna cnb cnc cnh cnn cny cya cyb cyc cyn haa hab hac hah han hay hba hbb hbc hbh hbn hby hca hcb hcc hch hcn hcy hha hhb hhc hhh hhn hhy hna hnb hnc hnh hnn hny hy- hya hyb hyc hyh hyn hyy naa nab nac nah nan nay nba nbb nbc nbn nca ncb ncc nch ncn nha nhb nhc nhh nhn nhy nna nnb nnc nnh nnn nya nyc nyn nyy yaa yab yac yah yan yay ybc yby yca ycc ych ycy yha yhc yna ynn yny yyb yyc yyy