a-a a-t aaa aaf aag aao aat aax af- afa aff afg afo aft afx ag- aga agf agg ago agt agx aoa aof aog aoo aot aox at- ata atf atg ato att atx ax- axa axo axt axx faa faf fag fao fat fax ffa fff ffg ffo fft ffx fga fgf fgg fgt foa fof fog foo fot fox fta ftf ftg fto ftt ftx fxg fxt fxx gaa gaf gag gao gat gfa gff gfo gft gfx gga ggg ggo ggt goa gof gog goo got gox gta gtf gtg gto gtt gtx gxa gxf gxt oaa oaf oag oao oat oax of- ofa off ofg ofo oft ofx oga ogf ogg ogo ogt ogx oo- ooa oof oog ooo oot oox ot- ota otf otg oto ott ox- oxa oxf oxo oxt oxx t-x taa taf tag tao tat tax tfa tff tfg tfo tft tfx tga tgf tgg tgo tgt to- toa tof tog too tot tox tta ttf ttg tto ttt ttx txf txt xaa xaf xag xat xfa xft xfx xoa xof xog xoo xot xox xtf xtx xxo xxx