bbb bbe bbi bbl bbt bbx be- beb bee bei bel bet bex bi- bib bie bii bil bit bix blb ble bli bll blt blx btb bte bti btl btt btx bxb bxi bxl bxx ebb ebe ebi ebl ebt ebx eeb eee eel eet eex eib eie eii eil eit eix elb ele eli ell elt elx etb ete eti etl ett etx ex- exe exi exl ext exx ibb ibe ibi ibl ibt ibx ie- iee iei iel iet iex iib iie iii iil iit iix il- ilb ile ili ill ilt ilx itb ite iti itl itt itx ixe ixi ixl lbb lbe lbi lbl lbt lbx leb lee lei lel let lex lib lie lii lil lit lix llb lle lli lll llt ltb lte lti ltl ltt ltx lxi lxx t-x tbb tbe tbi tbl tbt te- teb tee tei tel tet tex tib tie tii til tit tix tle tli tll tlt tlx ttb tte tti ttl ttt ttx txe txi txl txt xbe xbl xbx xee xel xet xex xie xii xit xix xlb xli xlt xti xtx xxi xxl xxx