bbb bbe bbn bbs bbt bbx be- beb bee ben bes bet bex bnb bne bnn bns bnt bnx bsb bse bsn bss bst bsx btb bte btn bts btt btx bxb bxn bxx ebb ebe ebn ebs ebt ebx eeb eee een ees eet eex en- enb ene enn ens ent es- esb ese esn ess est esx etb ete etn ets ett etx ex- exe exs ext exx nbb nbe nbn nbs nbt nbx ne- neb nee nen nes net nex nnb nne nnn nns nnt nsb nse nsn nss nst nsx ntb nte ntn nts ntt ntx nxt sbb sbe sbn sbs sbt sbx se- seb see sen ses set sex snb sne snn sns snt ss- ssb sse ssn sss sst ssx stb ste stn sts stt stx sxn sxs sxt t-x tbb tbe tbn tbs tbt te- teb tee ten tes tet tex tnb tne tnn tns tnt tnx tsb tse tsn tss tst tsx ttb tte ttn tts ttt ttx txe txn txs txt xbe xbx xee xen xes xet xex xns xsb xss xst xts xtx xxx