a-a a-b aaa aab aah aan aao aar aas ab- aba abb abh abn abo abr abs aha ahb ahh ahn aho ahr ahs an- ana anb anh ann ano anr ans aoa aob aoh aon aoo aor aos ar- ara arb arh arn aro arr ars as- asa asb ash asn aso asr ass baa bab bah ban bao bar bas bba bbb bbh bbn bbo bbr bbs bha bhb bhh bho bhr bhs bna bnb bnn bno bnr bns boa bob boh bon boo bor bos bra brb brh brn bro brr brs bsa bsb bsh bsn bso bsr bss haa hab hah han hao har has hba hbb hbh hbn hbo hbr hbs hha hhb hhh hhn hho hhr hhs hna hnb hnh hnn hno hns hoa hob hoh hon hoo hor hos hr- hra hrb hrh hrn hro hrr hrs hsa hsb hsh hsn hsr hss naa nab nah nan nao nar nas nba nbb nbn nbo nbr nbs nha nhb nhh nhn nhr nhs nna nnb nnh nnn nno nns no- noa nob noh non noo nor nos nra nrb nrn nro nrr nrs nsa nsb nsh nsn nso nsr nss oaa oab oah oan oao oar oas ob- oba obb obh obn obo obr obs oha ohh ohn oho ohr ohs on- ona onb onh onn ono onr ons oo- ooa oob ooh oon ooo oor oos or- ora orb orh orn oro orr ors os- osa osb osh osn oso osr oss ra- raa rab rah ran rao rar ras rba rbb rbh rbn rbo rbr rbs rh- rha rhb rhh rhn rho rhr rhs rna rnb rnh rnn rno rnr rns roa rob roh ron roo ror ros rra rrb rrh rrn rrr rrs rsa rsb rsh rsn rso rsr rss saa sab sah san sao sar sas sba sbb sbh sbn sbo sbr sbs sh- sha shb shh shn sho shr shs sna snb snn sno snr sns soa sob soh son soo sor sos sr- sra srb srh srn sro srr srs ss- ssa ssb ssh ssn sso ssr sss