-ic a-a a-b a-c a-i aaa aab aac aai aak aan aar aas ab- aba abb abc abi abk abn abr abs ac- aca acb acc aci ack acn acr acs ai- aia aib aic aii aik ain air ais aka akb akc aki akk akn akr aks an- ana anb anc ani ank ann anr ans ar- ara arb arc ari ark arn arr ars as- asa asb asc asi ask asn asr ass baa bab bac bai bak ban bar bas bba bbb bbc bbi bbk bbn bbr bbs bca bcb bcc bci bck bcn bcr bcs bi- bia bib bic bii bik bin bir bis bka bkb bkc bkk bkn bkr bks bna bnb bnc bni bnk bnn bnr bns bra brb bri brk brn brr brs bsa bsb bsc bsi bsk bsn bsr bss c-- caa cab cac cai cak can car cas cba cbb cbc cbi cbk cbn cbr cbs cca ccb ccc cci cck ccn ccr ccs ci- cia cib cic cii cik cin cir cis cka ckb ckc cki cks cn- cna cnb cnc cni cnn cnr cns cra crb crc cri crk crn crr crs csa csb csc csi csk csn csr css ia- iaa iab iac iai ian iar ias iba ibb ibc ibi ibk ibn ibr ibs ica icb icc ici ick icn icr ics iia iib iic iii iin iir iis ika ikb ikc iki ikk ikr iks in- ina inb inc ini ink inn inr ins ir- ira irb irc iri irk irn irr irs is- isa isb isc isi isk isn isr iss ka- kaa kab kac kai kak kan kar kas kba kbb kbc kbi kbk kbn kbr kbs kca kcb kcc kci kck kcn kcr kcs kia kib kic kii kik kin kir kis kkb kkc kki kkk kkn kkr kks kn- kna knc kni knk knn knr kra krc kri krk krn krr krs ksa ksb ksc ksi ksk ksn ksr kss n-i naa nab nac nai nak nan nar nas nba nbb nbc nbi nbk nbn nbr nbs nca ncb ncc nci nck ncn ncr ncs nia nib nic nii nik nin nir nis nka nkc nki nkk nkn nkr nks nna nnb nnc nni nnk nnn nns nra nrb nrc nri nrk nrn nrr nrs nsa nsb nsc nsi nsk nsn nsr nss ra- raa rab rac rai rak ran rar ras rba rbb rbc rbi rbk rbn rbr rbs rca rcb rcc rci rcn rcr rcs ria rib ric rii rik rin rir ris rkb rkc rkk rks rna rnb rnc rni rnn rnr rns rra rrb rrc rri rrk rrn rrr rrs rsa rsb rsc rsi rsk rsn rsr rss saa sab sac sai sak san sar sas sba sbb sbc sbi sbk sbn sbr sbs sca scb scc sci sck scn scr scs sia sib sic sii sik sin sir sis sk- ska skb skc ski skk skr sks sna snb snc sni snk snn snr sns sr- sra srb src sri srk srn srr srs ss- ssa ssb ssc ssi ssk ssn ssr sss