-th a-a a-b a-t aaa aab aag aah aan aat ab- aba abb abg abh abn abt ag- aga agb agg agh agn agt aha ahb ahg ahh ahn aht an- ana anb ang anh ann ant at- ata atb atg ath atn att baa bab bag bah ban bat bba bbb bbg bbh bbn bbt bga bgb bgg bgh bgn bgt bha bhb bhg bhh bht bna bnb bng bnn bnt bta btb btg bth btn btt gaa gab gag gah gan gat gba gbg gbh gbn gbt gga ggb ggg ggh ggn ggt gha ghb ghg ghh ghn ght gna gnb gnn gnt gta gtb gtg gth gtn gtt haa hab hag hah han hat hba hbb hbg hbh hbn hbt hga hgb hgg hgh hgn hgt hha hhb hhg hhh hhn hht hna hnb hng hnh hnn hnt hta htb htg hth htn htt naa nab nag nah nan nat nba nbb nbg nbn nbt nga ngb ngg ngh ngn ngt nha nhb nhg nhh nhn nht nna nnb nng nnh nnn nnt nta ntb ntg nth ntn ntt taa tab tag tah tan tat tba tbb tbg tbh tbn tbt tga tgb tgg tgh tgn tgt th- tha thb thg thh thn tht tna tnb tng tnh tnn tnt tta ttb ttg tth ttn ttt