a-a a-b a-i aaa aab aae aai aam aax ab- aba abb abe abi abm abx aea aeb aee aei aem aex ai- aia aib aie aii aim aix ama amb ame ami amm amx ax- axa axe axi axm axx baa bab bae bai bam bax bba bbb bbe bbi bbm bbx be- bea beb bee bei bem bex bi- bia bib bie bii bim bix bma bmb bme bmi bmm bmx bxb bxi bxm bxx eaa eab eae eai eam eax eba ebb ebe ebi ebm ebx eea eeb eee eem eex eia eib eie eii eim eix em- ema emb eme emi emm emx ex- exa exe exi exx ia- iaa iab iae iai iam iba ibb ibe ibi ibm ibx ie- iea iee iei iem iex iia iib iie iii iim iix im- ima imb ime imi imm imx ixe ixi maa mab mae mai mam max mba mbb mbe mbi mbm mbx mea meb mee mei mem mex mi- mia mib mie mii mim mix mma mmb mme mmi mmm mmx mxa mxi xaa xam xbe xbx xee xem xex xia xie xii xix xma xmi xmm xmx xxi xxx