a-a a-b a-t aaa aab aae aaf aan aao aat ab- aba abb abe abf abn abo abt aea aeb aee aef aen aeo aet af- afa afb afe aff afn afo aft an- ana anb ane anf ann ano ant aoa aob aoe aof aon aoo aot at- ata atb ate atf atn ato att baa bab bae baf ban bao bat bba bbb bbe bbf bbn bbo bbt be- bea beb bee bef ben beo bet bfa bfb bfe bff bfn bfo bft bna bnb bne bnf bnn bno bnt boa bob boe bof bon boo bot bta btb bte btf btn bto btt eaa eab eae eaf ean eao eat eba ebb ebe ebf ebn ebo ebt eea eeb eee eef een eeo eet ef- efa efb efe eff efo eft en- ena enb ene enf enn eno ent eo- eoa eob eoe eof eon eoo eot eta etb ete etf etn eto ett faa fab fae faf fan fao fat fba fbb fbe fbf fbn fbo fbt fea feb fee fef fen feo fet ffa ffe fff ffn ffo fft fna fnb fne fnf fnn fnt foa fob foe fof fon foo fot fta ftb fte ftf ftn fto ftt naa nab nae naf nan nao nat nba nbb nbe nbf nbn nbo nbt ne- nea neb nee nef nen neo net nfa nfb nfe nff nfn nfo nft nna nnb nne nnf nnn nno nnt no- noa nob noe nof non noo not nta ntb nte ntf ntn nto ntt oaa oab oae oaf oan oao oat ob- oba obb obe obf obn obo obt oea oeb oee oef oen oeo oet of- ofa ofb ofe off ofn ofo oft on- ona onb one onf onn ono ont oo- ooa oob oof oon ooo oot ot- ota otb ote otf otn oto ott taa tab tae taf tan tao tat tba tbb tbe tbf tbn tbo tbt te- tea teb tee tef ten teo tet tfa tfb tfe tff tfn tfo tft tna tnb tne tnf tnn tno tnt to- toa tob toe tof ton too tot tta ttb tte ttf ttn tto ttt