bbb bbe bbi bbn bbs bbt bbx be- beb bee bei ben bes bet bex bi- bib bie bii bin bis bit bix bnb bne bni bnn bns bnt bnx bsb bse bsi bsn bss bst bsx btb bte bti btn bts btt btx bxb bxi bxn bxx ebb ebe ebi ebn ebs ebt ebx eeb eee een ees eet eex eib eie eii ein eis eit eix en- enb ene eni enn ens ent es- esb ese esi esn ess est esx etb ete eti etn ets ett etx ex- exe exi exs ext exx ibb ibe ibi ibn ibs ibt ibx ie- iee iei ien ies iet iex iib iie iii iin iis iit iix in- inb ine ini inn ins int inx is- isb ise isi isn iss ist itb ite iti itn its itt itx ixe ixi ixn n-i nbb nbe nbi nbn nbs nbt nbx ne- neb nee nei nen nes net nex nib nie nii nin nis nit nix nnb nne nni nnn nns nnt nsb nse nsi nsn nss nst nsx ntb nte nti ntn nts ntt ntx nxt sbb sbe sbi sbn sbs sbt sbx se- seb see sei sen ses set sex sib sie sii sin sis sit six snb sne sni snn sns snt ss- ssb sse ssi ssn sss sst ssx stb ste sti stn sts stt stx sxi sxn sxs sxt t-x tbb tbe tbi tbn tbs tbt te- teb tee tei ten tes tet tex tib tie tii tin tis tit tix tnb tne tni tnn tns tnt tnx tsb tse tsi tsn tss tst tsx ttb tte tti ttn tts ttt ttx txe txi txn txs txt xbe xbx xee xen xes xet xex xie xii xin xis xit xix xns xsb xsi xss xst xti xts xtx xxi xxx