fff ffk ffn ffo fft ffx fkf fkk fkt fnf fnk fnn fnt fnx fof fok fon foo fot fox ftf ftk ftn fto ftt ftx fxt fxx k-t kff kfo kfx kkk kkn kkt kn- knf knk knn kno knt knx kof kok kon koo kot ktf ktk ktn kto ktt kxo nff nfk nfn nfo nft nkf nkk nkn nko nkt nnf nnk nnn nno nnt no- nof nok non noo not nox ntf ntk ntn nto ntt ntx nxt of- off ofn ofo oft ofx okk oko on- onf onk onn ono ont onx oo- oof ook oon ooo oot oox ot- otf otk otn oto ott ox- oxf oxn oxo oxt oxx t-x tff tfk tfn tfo tft tfx tkk tko tkt tnf tnk tnn tno tnt tnx to- tof tok ton too tot tox ttf ttk ttn tto ttt ttx txf txk txn txt xfn xft xfx xnk xno xof xok xon xoo xot xox xtf xtx xxo xxx