a-a a-b a-q a-t aaa aab aae aaq aas aat aax ab- aba abb abe abq abs abt abx aea aeb aee aeq aes aet aex aqa aqs aqt as- asa asb ase asq ass ast asx at- ata atb ate ats att atx ax- axa axe axs axt axx baa bab bae baq bas bat bax bba bbb bbe bbq bbs bbt bbx be- bea beb bee beq bes bet bex bqe bqt bsa bsb bse bss bst bsx bta btb bte btq bts btt btx bxb bxq bxx eaa eab eae eas eat eax eba ebb ebe ebq ebs ebt ebx eea eeb eee ees eet eex eqa eqe eqq eqs eqt es- esa esb ese esq ess est esx eta etb ete ets ett etx ex- exa exe exs ext exx qaa qas qat qax qba qbe qbq qbs qee qet qex qqq qsa qst qta qtq qts qxe saa sab sae saq sas sat sax sba sbb sbe sbq sbs sbt sbx se- sea seb see seq ses set sex sqa sqq sqs sqx ss- ssa ssb sse ssq sss sst ssx sta stb ste stq sts stt stx sxs sxt t-x taa tab tae taq tas tat tax tba tbb tbe tbs tbt te- tea teb tee teq tes tet tex tsa tsb tse tsq tss tst tsx tta ttb tte tts ttt ttx txe txs txt xaa xas xat xbe xbx xee xeq xes xet xex xqt xsa xsb xss xst xts xtx xxx