a-a a-t aaa aaf aan aao aat af- afa aff afn afo aft an- ana anf ann ano ant aoa aof aon aoo aot at- ata atf atn ato att faa faf fan fao fat ffa fff ffn ffo fft fna fnf fnn fnt foa fof fon foo fot fta ftf ftn fto ftt naa naf nan nao nat nfa nff nfn nfo nft nna nnf nnn nno nnt no- noa nof non noo not nta ntf ntn nto ntt oaa oaf oan oao oat of- ofa off ofn ofo oft on- ona onf onn ono ont oo- ooa oof oon ooo oot ot- ota otf otn oto ott taa taf tan tao tat tfa tff tfn tfo tft tna tnf tnn tno tnt to- toa tof ton too tot tta ttf ttn tto ttt