a-a a-b a-i aaa aab aai aak aan aar aas ab- aba abb abi abk abn abr abs ai- aia aib aii aik ain air ais aka akb aki akk akn akr aks an- ana anb ani ank ann anr ans ar- ara arb ari ark arn arr ars as- asa asb asi ask asn asr ass baa bab bai bak ban bar bas bba bbb bbi bbk bbn bbr bbs bi- bia bib bii bik bin bir bis bka bkb bkk bkn bkr bks bna bnb bni bnk bnn bnr bns bra brb bri brk brn brr brs bsa bsb bsi bsk bsn bsr bss ia- iaa iab iai ian iar ias iba ibb ibi ibk ibn ibr ibs iia iib iii iin iir iis ika ikb iki ikk ikr iks in- ina inb ini ink inn inr ins ir- ira irb iri irk irn irr irs is- isa isb isi isk isn isr iss ka- kaa kab kai kak kan kar kas kba kbb kbi kbk kbn kbr kbs kia kib kii kik kin kir kis kkb kki kkk kkn kkr kks kn- kna kni knk knn knr kra kri krk krn krr krs ksa ksb ksi ksk ksn ksr kss n-i naa nab nai nak nan nar nas nba nbb nbi nbk nbn nbr nbs nia nib nii nik nin nir nis nka nki nkk nkn nkr nks nna nnb nni nnk nnn nns nra nrb nri nrk nrn nrr nrs nsa nsb nsi nsk nsn nsr nss ra- raa rab rai rak ran rar ras rba rbb rbi rbk rbn rbr rbs ria rib rii rik rin rir ris rkb rkk rks rna rnb rni rnn rnr rns rra rrb rri rrk rrn rrr rrs rsa rsb rsi rsk rsn rsr rss saa sab sai sak san sar sas sba sbb sbi sbk sbn sbr sbs sia sib sii sik sin sir sis sk- ska skb ski skk skr sks sna snb sni snk snn snr sns sr- sra srb sri srk srn srr srs ss- ssa ssb ssi ssk ssn ssr sss