-ic a-a a-b a-c a-i a-t aaa aab aac aai aat aax ab- aba abb abc abi abt abx ac- aca acb acc aci act acx ai- aia aib aic aii ait aix at- ata atb atc ati att atx ax- axa axi axt axx baa bab bac bai bat bax bba bbb bbc bbi bbt bbx bca bcb bcc bci bct bcx bi- bia bib bic bii bit bix bta btb btc bti btt btx bxb bxi bxx c-- caa cab cac cai cat cax cba cbb cbc cbi cbt cbx cca ccb ccc cci cct ccx ci- cia cib cic cii cit cix cta ctb ctc cti ctt ctx cxc cxi cxt cxx ia- iaa iab iac iai iat iba ibb ibc ibi ibt ibx ica icb icc ici ict iia iib iic iii iit iix ita itb itc iti itt itx ixc ixi t-x taa tab tac tai tat tax tba tbb tbc tbi tbt tca tcb tcc tci tct tcx tia tib tic tii tit tix tta ttb ttc tti ttt ttx txi txt xaa xac xat xbc xbx xcb xci xcx xia xic xii xit xix xtc xti xtx xxi xxx