a-a a-b a-i a-t aaa aab aag aai aas aat aay ab- aba abb abg abi abs abt aby ag- aga agb agg agi ags agt agy ai- aia aib aig aii ais ait aiy as- asa asb asg asi ass ast asy at- ata atb atg ati ats att ay- aya ayi ays ayt baa bab bag bai bas bat bay bba bbb bbg bbi bbs bbt bby bga bgb bgg bgi bgs bgt bi- bia bib big bii bis bit biy bsa bsb bsg bsi bss bst bsy bta btb btg bti bts btt bty by- bya byg byi bys byt gaa gab gag gai gas gat gay gba gbg gbi gbs gbt gby gga ggb ggg ggi ggs ggt gia gib gig gii gis git giy gsa gsb gsg gsi gss gst gta gtb gtg gti gts gtt gty gy- gya gyb gys ia- iaa iab iag iai ias iat iba ibb ibg ibi ibs ibt iby iga igb igg igi igs igt igy iia iib iii iis iit is- isa isb isg isi iss ist isy ita itb itg iti its itt ity iya iys iyt iyy saa sab sag sai sas sat say sba sbb sbg sbi sbs sbt sby sga sgb sgg sgi sgs sgt sia sib sig sii sis sit ss- ssa ssb ssg ssi sss sst sta stb stg sti sts stt sty sy- sya syb syg syi sys syt taa tab tag tai tas tat tay tba tbb tbg tbi tbs tbt tga tgb tgg tgi tgs tgt tgy tia tib tig tii tis tit tiy tsa tsb tsg tsi tss tst tsy tta ttb ttg tti tts ttt tty tya tyg tys tyt yaa yab yag yai yas yat yay ybg ybi ybs yby yga yig yii yis yit ysa ysb ysg ysi yss yst ysy yta yts ytt yyb yyg yys yyt yyy