a-a a-b a-c a-t aaa aab aac aae aan aat aau aax ab- aba abb abc abe abn abt abu abx ac- aca acb acc ace acn act acu acx aea aeb aec aee aen aet aeu aex an- ana anb anc ane ann ant anu anx at- ata atb atc ate atn att atu atx au- aua aub auc aue aun aut aux ax- axa axe axn axt axx b-u baa bab bac bae ban bat bau bax bba bbb bbc bbe bbn bbt bbu bbx bca bcb bcc bce bcn bct bcu bcx be- bea beb bec bee ben bet beu bex bna bnb bnc bne bnn bnt bnu bnx bta btb btc bte btn btt btu btx bua bub buc bue bun but buu bux bxb bxn bxx c-- caa cab cac cae can cat cau cax cba cbb cbc cbe cbn cbt cbu cbx cca ccb ccc cce ccn cct ccu ccx ce- cea ceb cec cee cen cet ceu cex cn- cna cnb cnc cne cnn cnt cnu cnx cta ctb ctc cte ctn ctt ctu ctx cua cub cuc cue cun cut cuu cxc cxt cxx eaa eab eac eae ean eat eau eax eba ebb ebc ebe ebn ebt ebu ebx ec- eca ecb ecc ece ecn ect ecu ecx eea eeb eec eee een eet eex en- ena enb enc ene enn ent enu eta etb etc ete etn ett etu etx eu- eua eub euc eue eun eut eux ex- exa exc exe ext exu exx naa nab nac nae nan nat nau nax nba nbb nbc nbe nbn nbt nbu nbx nca ncb ncc nce ncn nct ncu ncx ne- nea neb nec nee nen net neu nex nna nnb nnc nne nnn nnt nnu nta ntb ntc nte ntn ntt ntu ntx nua nub nuc nue nun nut nuu nux nxc nxt t-x taa tab tac tae tan tat tau tax tba tbb tbc tbe tbn tbt tbu tca tcb tcc tce tcn tct tcu tcx te- tea teb tec tee ten tet teu tex tna tnb tnc tne tnn tnt tnx tta ttb ttc tte ttn ttt ttu ttx tua tub tuc tue tun tut tuu tux txe txn txt txu ua- uaa uab uac uae uan uat uau uba ubb ubc ube ubn ubt ubu ubx uca ucb ucc uce ucn uct ucu uea ueb uec uee uen uet un- una unb unc une unn unt unu unx uta utb utc ute utn utt utu utx uua uuc uue uun uut uuu uxb uxc uxt uxu xaa xac xan xat xau xbc xbe xbx xcb xcx xee xen xet xeu xex xna xnc xnu xtc xtx xue xun xxx