-er bbb bbe bbf bbm bbn bbo bbr bbs bbx be- beb bee bef bem ben beo ber bes bex bfb bfe bff bfm bfn bfo bfr bfs bfx bmb bme bmf bmm bmn bmo bmr bms bmx bnb bne bnf bnn bno bnr bns bnx bob boe bof bom bon boo bor bos box brb bre brf brm brn bro brr brs brx bsb bse bsf bsm bsn bso bsr bss bsx bxb bxm bxn bxo bxx ebb ebe ebf ebm ebn ebo ebr ebs ebx eeb eee eef eem een eeo eer ees eex ef- efb efe eff efm efo efr efs efx em- emb eme emf emm emn emo emr ems emx en- enb ene enf enm enn eno enr ens eo- eob eoe eof eom eon eoo eor eos erb ere erf erm ern ero err ers es- esb ese esf esm esn eso esr ess esx ex- exe exo exr exs exx fbb fbe fbf fbm fbn fbo fbr fbs fbx feb fee fef fem fen feo fer fes fex ffe fff ffm ffn ffo ffr ffs ffx fmb fme fmf fmm fmn fmo fmr fms fmx fnb fne fnf fnm fnn fnr fns fnx fob foe fof fom fon foo for fos fox frb fre frf frm frn fro frr frs fsb fse fsf fsm fsn fso fsr fss fsx fxe fxm fxr fxs fxx m-f m-o m-r mbb mbe mbf mbm mbo mbr mbs mbx meb mee mef mem men meo mer mes mex mfb mfe mff mfm mfn mfo mfr mfs mmb mme mmf mmm mmn mmo mmr mms mmx mnb mne mnf mnm mnn mno mnr mns mob moe mof mom mon moo mor mos mox mrb mre mrf mrm mrn mro mrr mrs mrx msb mse msf msm msn mso msr mss msx mxn mxr mxs nbb nbe nbf nbm nbn nbo nbr nbs nbx ne- neb nee nef nem nen neo ner nes nex nfb nfe nff nfn nfo nfr nfs nmb nme nmm nmn nmo nmr nms nnb nne nnf nnm nnn nno nns no- nob noe nof nom non noo nor nos nox nrb nre nrf nrm nrn nro nrr nrs nrx nsb nse nsf nsm nsn nso nsr nss nsx ob- obb obe obf obm obn obo obr obs obx oeb oee oef oem oen oeo oer oes oex of- ofb ofe off ofm ofn ofo ofr ofs ofx om- omb ome omf omm omn omo omr oms omx on- onb one onf onn ono onr ons onx oo- oob oof oom oon ooo oor oos oox or- orb ore orf orm orn oro orr ors orx os- osb ose osf osm osn oso osr oss osx ox- oxb oxf oxn oxo oxx rbb rbe rbf rbm rbn rbo rbr rbs rbx re- reb ree ref rem ren reo rer res rex rfb rfe rff rfm rfn rfo rfr rfs rmb rme rmf rmm rmn rmo rmr rms rmx rnb rnm rnn rno rnr rns rob roe rof rom ron roo ror ros rox rrb rrf rrm rrn rrr rrs rsb rse rsf rsm rsn rso rsr rss rsx rxr rxs sbb sbe sbf sbm sbn sbo sbr sbs sbx se- seb see sef sem sen seo ser ses sex sfb sfe sff sfm sfn sfo sfr sfs sfx smb sme smf smm smn smo smr sms smx snb sne snf snm snn sno snr sns sob soe sof som son soo sor sos sox sr- srb sre srf srm srn sro srr srs srx ss- ssb sse ssf ssm ssn sso ssr sss ssx sxm sxn sxs xbe xbr xbx xee xem xen xer xes xex xfe xfm xfn xfs xfx xmf xmm xmo xmr xms xmx xno xns xof xom xon xoo xor xos xox xrf xrx xsb xsm xss xxo xxx