a-a a-b a-t aaa aab aag aas aat aay ab- aba abb abg abs abt aby ag- aga agb agg ags agt agy as- asa asb asg ass ast asy at- ata atb atg ats att ay- aya ays ayt baa bab bag bas bat bay bba bbb bbg bbs bbt bby bga bgb bgg bgs bgt bsa bsb bsg bss bst bsy bta btb btg bts btt bty by- bya byg bys byt gaa gab gag gas gat gay gba gbg gbs gbt gby gga ggb ggg ggs ggt gsa gsb gsg gss gst gta gtb gtg gts gtt gty gy- gya gyb gys saa sab sag sas sat say sba sbb sbg sbs sbt sby sga sgb sgg sgs sgt ss- ssa ssb ssg sss sst sta stb stg sts stt sty sy- sya syb syg sys syt taa tab tag tas tat tay tba tbb tbg tbs tbt tga tgb tgg tgs tgt tgy tsa tsb tsg tss tst tsy tta ttb ttg tts ttt tty tya tyg tys tyt yaa yab yag yas yat yay ybg ybs yby yga ysa ysb ysg yss yst ysy yta yts ytt yyb yyg yys yyt yyy