a-a a-b a-t aaa aab aak aan aao aas aat ab- aba abb abk abn abo abs abt aka akb akk akn ako aks an- ana anb ank ann ano ans ant aoa aob aok aon aoo aos aot as- asa asb ask asn aso ass ast at- ata atb atn ato ats att baa bab bak ban bao bas bat bba bbb bbk bbn bbo bbs bbt bka bkb bkk bkn bko bks bkt bna bnb bnk bnn bno bns bnt boa bob bok bon boo bos bot bsa bsb bsk bsn bso bss bst bta btb btk btn bto bts btt k-t ka- kaa kab kak kan kao kas kat kba kbb kbk kbn kbo kbs kkb kkk kkn kks kkt kn- kna knk knn kno knt koa kob kok kon koo kos kot ksa ksb ksk ksn kso kss kst kta ktb ktk ktn kto kts ktt naa nab nak nan nao nas nat nba nbb nbk nbn nbo nbs nbt nka nkk nkn nko nks nkt nna nnb nnk nnn nno nns nnt no- noa nob nok non noo nos not nsa nsb nsk nsn nso nss nst nta ntb ntk ntn nto nts ntt oaa oab oak oan oao oas oat ob- oba obb obk obn obo obs obt oka okb okk oko oks on- ona onb onk onn ono ons ont oo- ooa oob ook oon ooo oos oot os- osa osb osk osn oso oss ost ot- ota otb otk otn oto ots ott saa sab sak san sao sas sat sba sbb sbk sbn sbo sbs sbt sk- ska skb skk sko sks skt sna snb snk snn sno sns snt soa sob sok son soo sos sot ss- ssa ssb ssk ssn sso sss sst sta stb stk stn sto sts stt taa tab tak tan tao tas tat tba tbb tbk tbn tbo tbs tbt tka tkb tkk tko tks tkt tna tnb tnk tnn tno tns tnt to- toa tob tok ton too tos tot tsa tsb tsk tsn tso tss tst tta ttb ttk ttn tto tts ttt