a-a aaa aaf aag aao aar aax aay af- afa aff afg afo afr afx afy ag- aga agf agg ago agr agx agy aoa aof aog aoo aor aox ar- ara arf arg aro arr arx ary ax- axa axo axr axx ay- aya ayf ayo ayr ayx faa faf fag fao far fax fay ffa fff ffg ffo ffr ffx ffy fga fgf fgg fgr foa fof fog foo for fox foy fra frf frg fro frr fry fxg fxr fxx fy- fya fyo gaa gaf gag gao gar gay gfa gff gfo gfr gfx gfy gga ggg ggo ggr goa gof gog goo gor gox goy gra grf grg gro grr grx gry gxa gxf gy- gya gyf gyo gyr oaa oaf oag oao oar oax of- ofa off ofg ofo ofr ofx oga ogf ogg ogo ogx ogy oo- ooa oof oog ooo oor oox or- ora orf org oro orr orx ory ox- oxa oxf oxo oxx oxy oya oyo ra- raa raf rag rao rar rax ray rfa rff rfg rfo rfr rga rgf rgg rgo rgr rgx roa rof rog roo ror rox roy rra rrf rrg rrr rxr ry- rya ryf ryg ryo ryr ryy xaa xaf xag xar xfa xfx xoa xof xog xoo xor xox xrf xrx xry xxo xxx xxy xyr xyy yaa yaf yag yao yar yax yay yfa yff yfr yga ygo yof yog yoo yor yox yoy yra yrf yrg yro yxa yxy yyf yyg yyy