a-a a-b aaa aab aah aak aan aao aar aas ab- aba abb abh abk abn abo abr abs aha ahb ahh ahk ahn aho ahr ahs aka akb akh akk akn ako akr aks an- ana anb anh ank ann ano anr ans aoa aob aoh aok aon aoo aor aos ar- ara arb arh ark arn aro arr ars as- asa asb ash ask asn aso asr ass baa bab bah bak ban bao bar bas bba bbb bbh bbk bbn bbo bbr bbs bha bhb bhh bhk bho bhr bhs bka bkb bkk bkn bko bkr bks bna bnb bnk bnn bno bnr bns boa bob boh bok bon boo bor bos bra brb brh brk brn bro brr brs bsa bsb bsh bsk bsn bso bsr bss haa hab hah hak han hao har has hba hbb hbh hbk hbn hbo hbr hbs hha hhb hhh hhk hhn hho hhr hhs hka hkb hkh hkk hkn hko hkr hks hna hnb hnh hnk hnn hno hns hoa hob hoh hok hon hoo hor hos hr- hra hrb hrh hrk hrn hro hrr hrs hsa hsb hsh hsk hsn hsr hss ka- kaa kab kah kak kan kao kar kas kba kbb kbh kbk kbn kbo kbr kbs kha khh khk khn kho khr khs kkb kkh kkk kkn kkr kks kn- kna knk knn kno knr koa kob koh kok kon koo kor kos kra krk krn kro krr krs ksa ksb ksh ksk ksn kso ksr kss naa nab nah nak nan nao nar nas nba nbb nbk nbn nbo nbr nbs nha nhb nhh nhk nhn nhr nhs nka nkk nkn nko nkr nks nna nnb nnh nnk nnn nno nns no- noa nob noh nok non noo nor nos nra nrb nrk nrn nro nrr nrs nsa nsb nsh nsk nsn nso nsr nss oaa oab oah oak oan oao oar oas ob- oba obb obh obk obn obo obr obs oha ohh ohn oho ohr ohs oka okb okk oko okr oks on- ona onb onh onk onn ono onr ons oo- ooa oob ooh ook oon ooo oor oos or- ora orb orh ork orn oro orr ors os- osa osb osh osk osn oso osr oss ra- raa rab rah rak ran rao rar ras rba rbb rbh rbk rbn rbo rbr rbs rh- rha rhb rhh rhn rho rhr rhs rkb rkk rko rks rna rnb rnh rnn rno rnr rns roa rob roh rok ron roo ror ros rra rrb rrh rrk rrn rrr rrs rsa rsb rsh rsk rsn rso rsr rss saa sab sah sak san sao sar sas sba sbb sbh sbk sbn sbo sbr sbs sh- sha shb shh shk shn sho shr shs sk- ska skb skh skk sko skr sks sna snb snk snn sno snr sns soa sob soh sok son soo sor sos sr- sra srb srh srk srn sro srr srs ss- ssa ssb ssh ssk ssn sso ssr sss