-ic a-a a-b a-c a-i a-t aaa aab aac aai aan aas aat ab- aba abb abc abi abn abs abt ac- aca acb acc aci acn acs act ai- aia aib aic aii ain ais ait an- ana anb anc ani ann ans ant as- asa asb asc asi asn ass ast at- ata atb atc ati atn ats att baa bab bac bai ban bas bat bba bbb bbc bbi bbn bbs bbt bca bcb bcc bci bcn bcs bct bi- bia bib bic bii bin bis bit bna bnb bnc bni bnn bns bnt bsa bsb bsc bsi bsn bss bst bta btb btc bti btn bts btt c-- caa cab cac cai can cas cat cba cbb cbc cbi cbn cbs cbt cca ccb ccc cci ccn ccs cct ci- cia cib cic cii cin cis cit cn- cna cnb cnc cni cnn cns cnt csa csb csc csi csn css cst cta ctb ctc cti ctn cts ctt ia- iaa iab iac iai ian ias iat iba ibb ibc ibi ibn ibs ibt ica icb icc ici icn ics ict iia iib iic iii iin iis iit in- ina inb inc ini inn ins int is- isa isb isc isi isn iss ist ita itb itc iti itn its itt n-i naa nab nac nai nan nas nat nba nbb nbc nbi nbn nbs nbt nca ncb ncc nci ncn ncs nct nia nib nic nii nin nis nit nna nnb nnc nni nnn nns nnt nsa nsb nsc nsi nsn nss nst nta ntb ntc nti ntn nts ntt saa sab sac sai san sas sat sba sbb sbc sbi sbn sbs sbt sca scb scc sci scn scs sct sia sib sic sii sin sis sit sna snb snc sni snn sns snt ss- ssa ssb ssc ssi ssn sss sst sta stb stc sti stn sts stt taa tab tac tai tan tas tat tba tbb tbc tbi tbn tbs tbt tca tcb tcc tci tcn tcs tct tia tib tic tii tin tis tit tna tnb tnc tni tnn tns tnt tsa tsb tsc tsi tsn tss tst tta ttb ttc tti ttn tts ttt