a-a a-b a-t aaa aab aak aan aao aar aas aat ab- aba abb abk abn abo abr abs abt aka akb akk akn ako akr aks an- ana anb ank ann ano anr ans ant aoa aob aok aon aoo aor aos aot ar- ara arb ark arn aro arr ars art as- asa asb ask asn aso asr ass ast at- ata atb atn ato atr ats att baa bab bak ban bao bar bas bat bba bbb bbk bbn bbo bbr bbs bbt bka bkb bkk bkn bko bkr bks bkt bna bnb bnk bnn bno bnr bns bnt boa bob bok bon boo bor bos bot bra brb brk brn bro brr brs brt bsa bsb bsk bsn bso bsr bss bst bta btb btk btn bto btr bts btt k-t ka- kaa kab kak kan kao kar kas kat kba kbb kbk kbn kbo kbr kbs kkb kkk kkn kkr kks kkt kn- kna knk knn kno knr knt koa kob kok kon koo kor kos kot kra krk krn kro krr krs krt ksa ksb ksk ksn kso ksr kss kst kta ktb ktk ktn kto ktr kts ktt naa nab nak nan nao nar nas nat nba nbb nbk nbn nbo nbr nbs nbt nka nkk nkn nko nkr nks nkt nna nnb nnk nnn nno nns nnt no- noa nob nok non noo nor nos not nra nrb nrk nrn nro nrr nrs nrt nsa nsb nsk nsn nso nsr nss nst nta ntb ntk ntn nto ntr nts ntt oaa oab oak oan oao oar oas oat ob- oba obb obk obn obo obr obs obt oka okb okk oko okr oks on- ona onb onk onn ono onr ons ont oo- ooa oob ook oon ooo oor oos oot or- ora orb ork orn oro orr ors ort os- osa osb osk osn oso osr oss ost ot- ota otb otk otn oto otr ots ott ra- raa rab rak ran rao rar ras rat rba rbb rbk rbn rbo rbr rbs rbt rkb rkk rko rks rkt rna rnb rnn rno rnr rns rnt roa rob rok ron roo ror ros rot rra rrb rrk rrn rrr rrs rrt rsa rsb rsk rsn rso rsr rss rst rta rtb rtk rtn rto rtr rts rtt saa sab sak san sao sar sas sat sba sbb sbk sbn sbo sbr sbs sbt sk- ska skb skk sko skr sks skt sna snb snk snn sno snr sns snt soa sob sok son soo sor sos sot sr- sra srb srk srn sro srr srs srt ss- ssa ssb ssk ssn sso ssr sss sst sta stb stk stn sto str sts stt taa tab tak tan tao tar tas tat tba tbb tbk tbn tbo tbr tbs tbt tka tkb tkk tko tkr tks tkt tna tnb tnk tnn tno tnr tns tnt to- toa tob tok ton too tor tos tot tra trb trk trn tro trr trs trt tsa tsb tsk tsn tso tsr tss tst tta ttb ttk ttn tto ttr tts ttt