-ic a-a a-b a-c a-i aaa aab aac aai aak aan aar ab- aba abb abc abi abk abn abr ac- aca acb acc aci ack acn acr ai- aia aib aic aii aik ain air aka akb akc aki akk akn akr an- ana anb anc ani ank ann anr ar- ara arb arc ari ark arn arr baa bab bac bai bak ban bar bba bbb bbc bbi bbk bbn bbr bca bcb bcc bci bck bcn bcr bi- bia bib bic bii bik bin bir bka bkb bkc bkk bkn bkr bna bnb bnc bni bnk bnn bnr bra brb bri brk brn brr c-- caa cab cac cai cak can car cba cbb cbc cbi cbk cbn cbr cca ccb ccc cci cck ccn ccr ci- cia cib cic cii cik cin cir cka ckb ckc cki cn- cna cnb cnc cni cnn cnr cra crb crc cri crk crn crr ia- iaa iab iac iai ian iar iba ibb ibc ibi ibk ibn ibr ica icb icc ici ick icn icr iia iib iic iii iin iir ika ikb ikc iki ikk ikr in- ina inb inc ini ink inn inr ir- ira irb irc iri irk irn irr ka- kaa kab kac kai kak kan kar kba kbb kbc kbi kbk kbn kbr kca kcb kcc kci kck kcn kcr kia kib kic kii kik kin kir kkb kkc kki kkk kkn kkr kn- kna knc kni knk knn knr kra krc kri krk krn krr n-i naa nab nac nai nak nan nar nba nbb nbc nbi nbk nbn nbr nca ncb ncc nci nck ncn ncr nia nib nic nii nik nin nir nka nkc nki nkk nkn nkr nna nnb nnc nni nnk nnn nra nrb nrc nri nrk nrn nrr ra- raa rab rac rai rak ran rar rba rbb rbc rbi rbk rbn rbr rca rcb rcc rci rcn rcr ria rib ric rii rik rin rir rkb rkc rkk rna rnb rnc rni rnn rnr rra rrb rrc rri rrk rrn rrr