bbb bbf bbn bbo bbt bby bfb bff bfn bfo bft bfy bnb bnf bnn bno bnt bob bof bon boo bot boy btb btf btn bto btt bty by- byf byn byo byt fbb fbf fbn fbo fbt fff ffn ffo fft ffy fnb fnf fnn fnt fob fof fon foo fot foy ftb ftf ftn fto ftt fty fy- fyb fyn fyo nbb nbf nbn nbo nbt nfb nff nfn nfo nft nnb nnf nnn nno nnt no- nob nof non noo not noy ntb ntf ntn nto ntt nyf nyn nyo nyt nyy ob- obb obf obn obo obt oby of- ofb off ofn ofo oft on- onb onf onn ono ont ony oo- oob oof oon ooo oot ot- otb otf otn oto ott oyo tbb tbf tbn tbo tbt tfb tff tfn tfo tft tnb tnf tnn tno tnt to- tob tof ton too tot toy ttb ttf ttn tto ttt tty tyf tyn tyo tyt ybf yby yff yft ynn yny yob yof yon yoo yot yoy ytf ytn yto ytt yyb yyf yyt yyy