a-a a-b aaa aab aae aag aan aau aax ab- aba abb abe abg abn abu abx aea aeb aee aeg aen aeu aex ag- aga agb age agg agn agu agx an- ana anb ane ang ann anu anx au- aua aub aue aug aun aux ax- axa axe axn axx b-u baa bab bae bag ban bau bax bba bbb bbe bbg bbn bbu bbx be- bea beb bee beg ben beu bex bga bgb bge bgg bgn bgu bgx bna bnb bne bng bnn bnu bnx bua bub bue bug bun buu bux bxb bxn bxx eaa eab eae eag ean eau eax eba ebb ebe ebg ebn ebu ebx eea eeb eee eeg een eex ega egb ege egg egn egu egx en- ena enb ene eng enn enu eu- eua eub eue eug eun eux ex- exa exe exu exx gaa gab gae gag gan gau gba gbe gbg gbn gbu gbx ge- gea geb gee geg gen geu gex gga ggb ggg ggn ggu gna gnb gne gnn gnu gu- gua gub gue gug gun guu gxa naa nab nae nag nan nau nax nba nbb nbe nbg nbn nbu nbx ne- nea neb nee neg nen neu nex nga ngb nge ngg ngn ngu nna nnb nne nng nnn nnu nua nub nue nug nun nuu nux ua- uaa uab uae uag uan uau uba ubb ube ubg ubn ubu ubx uea ueb uee ueg uen uga ugb uge ugg ugn ugu ugx un- una unb une ung unn unu unx uua uue uug uun uuu uxb uxu xaa xag xan xau xbe xbx xee xeg xen xeu xex xge xna xnu xue xun xxx