a-a a-b aaa aab aad aak aan aao aar aas aau ab- aba abb abd abk abn abo abr abs abu ad- ada adb add adk adn ado adr ads adu aka akb akd akk akn ako akr aks aku an- ana anb and ank ann ano anr ans anu aoa aob aod aok aon aoo aor aos aou ar- ara arb ard ark arn aro arr ars aru as- asa asb asd ask asn aso asr ass asu au- aua aub aud auk aun auo aur aus b-u baa bab bad bak ban bao bar bas bau bba bbb bbd bbk bbn bbo bbr bbs bbu bda bdb bdd bdk bdo bdr bds bdu bka bkb bkk bkn bko bkr bks bna bnb bnd bnk bnn bno bnr bns bnu boa bob bod bok bon boo bor bos bou bra brb brd brk brn bro brr brs bru bsa bsb bsd bsk bsn bso bsr bss bsu bua bub bud buk bun buo bur bus buu daa dab dad dak dan dao dar das dau dba dbb dbd dbk dbn dbo dbr dbs dbu dda ddb ddd ddk ddn ddo ddr dds ddu dka dkb dkk dko dkr dks dku dna dnb dnd dnk dnn dno dnr dns doa dob dod dok don doo dor dos dou dra drb drd drk drn dro drr drs dru dsa dsb dsd dsk dsn dso dsr dss dsu dua dub dud duk dun duo dur dus ka- kaa kab kad kak kan kao kar kas kau kba kbb kbd kbk kbn kbo kbr kbs kbu kda kdb kdk kdo kdr kds kdu kkb kkk kkn kkr kks kku kn- kna knd knk knn kno knr knu koa kob kod kok kon koo kor kos kou kra krd krk krn kro krr krs kru ksa ksb ksd ksk ksn kso ksr kss ksu kub kud kuk kun kur kus kuu naa nab nad nak nan nao nar nas nau nba nbb nbd nbk nbn nbo nbr nbs nbu nda ndb ndd ndk ndn ndo ndr nds ndu nka nkk nkn nko nkr nks nku nna nnb nnk nnn nno nns nnu no- noa nob nod nok non noo nor nos nou nra nrb nrd nrk nrn nro nrr nrs nru nsa nsb nsd nsk nsn nso nsr nss nsu nua nub nud nuk nun nuo nur nus nuu oaa oab oad oak oan oao oar oas oau ob- oba obb obd obk obn obo obr obs obu oda odb odd odn odo odr ods odu oka okb okd okk oko okr oks oku on- ona onb ond onk onn ono onr ons onu oo- ooa oob ood ook oon ooo oor oos or- ora orb ord ork orn oro orr ors oru os- osa osb osd osk osn oso osr oss osu ou- oua oud ouk oun ouo our ous ra- raa rab rad rak ran rao rar ras rau rba rbb rbd rbk rbn rbo rbr rbs rbu rda rdb rdd rdn rdo rdr rds rdu rkb rkk rko rks rku rna rnb rnd rnn rno rnr rns rnu roa rob rod rok ron roo ror ros rou rra rrb rrd rrk rrn rrr rrs rru rsa rsb rsd rsk rsn rso rsr rss rsu rua rub rud ruk run ruo rur rus ruu saa sab sad sak san sao sar sas sau sba sbb sbd sbk sbn sbo sbr sbs sbu sda sdb sdd sdk sdn sdo sdr sds sdu sk- ska skb skd skk sko skr sks sku sna snb snd snk snn sno snr sns snu soa sob sod sok son soo sor sos sou sr- sra srb srd srk srn sro srr srs ss- ssa ssb ssd ssk ssn sso ssr sss ssu sua sub sud suk sun suo sur sus suu ua- uaa uab uad uak uan uao uar uas uau uba ubb ubk ubn ubo ubr ubs ubu uda udb udd udk udn udo udr uds udu uka ukb ukk ukn ukr uku un- una unb und unk unn uno unr uns unu uoa uob uod uok uon uoo uor uos ur- ura urb urd urk urn uro urr urs uru usa usb usd usk usn uso usr uss usu uua uun uur uus uuu