a-a a-b a-t aaa aab aae aam aat aax ab- aba abb abe abm abt abx aea aeb aee aem aet aex ama amb ame amm amt amx at- ata atb ate atm att atx ax- axa axe axm axt axx baa bab bae bam bat bax bba bbb bbe bbm bbt bbx be- bea beb bee bem bet bex bma bmb bme bmm bmt bmx bta btb bte btm btt btx bxb bxm bxx eaa eab eae eam eat eax eba ebb ebe ebm ebt ebx eea eeb eee eem eet eex em- ema emb eme emm emt emx eta etb ete etm ett etx ex- exa exe ext exx maa mab mae mam mat max mba mbb mbe mbm mbt mbx mea meb mee mem met mex mma mmb mme mmm mmt mmx mta mtb mte mtm mtt mtx mxa t-x taa tab tae tam tat tax tba tbb tbe tbm tbt te- tea teb tee tem tet tex tma tmb tme tmm tmt tmx tta ttb tte ttm ttt ttx txe txt xaa xam xat xbe xbx xee xem xet xex xma xmm xmt xmx xtm xtx xxx