a-a a-b a-i aaa aab aaf aai aak aan aar ab- aba abb abf abi abk abn abr af- afa afb aff afi afk afn afr ai- aia aib aif aii aik ain air aka akb aki akk akn akr an- ana anb anf ani ank ann anr ar- ara arb arf ari ark arn arr baa bab baf bai bak ban bar bba bbb bbf bbi bbk bbn bbr bfa bfb bff bfi bfn bfr bi- bia bib bif bii bik bin bir bka bkb bkf bkk bkn bkr bna bnb bnf bni bnk bnn bnr bra brb brf bri brk brn brr faa fab faf fai fak fan far fba fbb fbf fbi fbk fbn fbr ffa fff ffi ffk ffn ffr fia fib fif fii fik fin fir fka fkb fkf fki fkk fna fnb fnf fni fnk fnn fnr fra frb frf fri frk frn frr i-f ia- iaa iab iaf iai ian iar iba ibb ibf ibi ibk ibn ibr ifa ifb iff ifi ifn ifr iia iib iif iii iin iir ika ikb ikf iki ikk ikr in- ina inb inf ini ink inn inr ir- ira irb irf iri irk irn irr ka- kaa kab kaf kai kak kan kar kba kbb kbf kbi kbk kbn kbr kfa kff kfi kia kib kif kii kik kin kir kkb kki kkk kkn kkr kn- kna knf kni knk knn knr kra krf kri krk krn krr n-i naa nab naf nai nak nan nar nba nbb nbf nbi nbk nbn nbr nfa nfb nff nfi nfk nfn nfr nia nib nif nii nik nin nir nka nkf nki nkk nkn nkr nna nnb nnf nni nnk nnn nra nrb nrf nri nrk nrn nrr ra- raa rab raf rai rak ran rar rba rbb rbf rbi rbk rbn rbr rfa rfb rff rfi rfk rfn rfr ria rib rif rii rik rin rir rkb rkf rkk rna rnb rni rnn rnr rra rrb rrf rri rrk rrn rrr