-er bbb bbe bbf bbg bbi bbk bbn bbo bbr bbs be- beb bee bef beg bei bek ben beo ber bes bfb bfe bff bfg bfi bfn bfo bfr bfs bgb bge bgf bgg bgi bgk bgn bgo bgr bgs bi- bib bie bif big bii bik bin bio bir bis bkb bke bkf bkg bkk bkn bko bkr bks bnb bne bnf bng bni bnk bnn bno bnr bns bob boe bof bog boi bok bon boo bor bos brb bre brf brg bri brk brn bro brr brs bsb bse bsf bsg bsi bsk bsn bso bsr bss ebb ebe ebf ebg ebi ebk ebn ebo ebr ebs eeb eee eef eeg eek een eeo eer ees ef- efb efe eff efg efi efo efr efs egb ege egf egg egi egn ego egr egs eib eie eif eig eii eik ein eio eir eis ekb eke ekf ekg eki eko ekr eks en- enb ene enf eng eni enk enn eno enr ens eo- eob eoe eof eog eoi eok eon eoo eor eos erb ere erf erg eri erk ern ero err ers es- esb ese esf esg esi esk esn eso esr ess fbb fbe fbf fbg fbi fbk fbn fbo fbr fbs feb fee fef feg fei fek fen feo fer fes ffe fff ffg ffi ffk ffn ffo ffr ffs fgb fge fgf fgg fgi fgn fgr fgs fib fie fif fig fii fik fin fir fis fkb fkf fkg fki fkk fnb fne fnf fng fni fnk fnn fnr fns fob foe fof fog foi fok fon foo for fos frb fre frf frg fri frk frn fro frr frs fsb fse fsf fsg fsi fsk fsn fso fsr fss gbe gbf gbg gbi gbk gbn gbo gbr gbs ge- geb gee gef geg gei gek gen geo ger ges gfb gfe gff gfi gfk gfo gfr gfs ggb ggg ggi ggn ggo ggr ggs gib gie gif gig gii gik gin gio gir gis gkb gkn gko gks gnb gne gnf gni gnn gno gnr gns gob goe gof gog goi gok gon goo gor gos grb gre grf grg gri grk grn gro grr grs gsb gse gsf gsg gsi gsk gsn gso gsr gss i-f ibb ibe ibf ibg ibi ibk ibn ibo ibr ibs ie- iee ief ieg iei iek ien ier ies ifb ife iff ifg ifi ifn ifo ifr ifs igb ige igf igg igi igk ign igo igr igs iib iie iif iii iin iio iir iis ikb ike ikf iki ikk iko ikr iks in- inb ine inf ing ini ink inn ino inr ins io- iob ioe iof iog ioi ion ioo ior ios ir- irb ire irf irg iri irk irn iro irr irs is- isb ise isf isg isi isk isn iso isr iss kbb kbe kbf kbi kbk kbn kbo kbr kbs ke- keb kee kef keg kei kek ken keo ker kes kff kfg kfi kfo kfs kgb kgf kgi kgo kgs kib kie kif kig kii kik kin kio kir kis kkb kke kki kkk kkn kkr kks kn- kne knf kng kni knk knn kno knr kob koe kof kog koi kok kon koo kor kos krf krg kri krk krn kro krr krs ksb kse ksf ksg ksi ksk ksn kso ksr kss n-i nbb nbe nbf nbg nbi nbk nbn nbo nbr nbs ne- neb nee nef neg nei nek nen neo ner nes nfb nfe nff nfi nfk nfn nfo nfr nfs ngb nge ngf ngg ngi ngk ngn ngo ngs nib nie nif nig nii nik nin nio nir nis nke nkf nki nkk nkn nko nkr nks nnb nne nnf nng nni nnk nnn nno nns no- nob noe nof nog noi nok non noo nor nos nrb nre nrf nrg nri nrk nrn nro nrr nrs nsb nse nsf nsg nsi nsk nsn nso nsr nss o-i ob- obb obe obf obg obi obk obn obo obr obs oeb oee oef oeg oei oen oeo oer oes of- ofb ofe off ofg ofi ofn ofo ofr ofs oge ogf ogg ogi ogn ogo ogs oib oie oif oii oik oin oio oir ois okb oke okg oki okk oko okr oks on- onb one onf ong oni onk onn ono onr ons oo- oob oof oog ooi ook oon ooo oor oos or- orb ore orf org ori ork orn oro orr ors os- osb ose osf osg osi osk osn oso osr oss rbb rbe rbf rbg rbi rbk rbn rbo rbr rbs re- reb ree ref reg rei rek ren reo rer res rfb rfe rff rfg rfi rfk rfn rfo rfr rfs rgb rge rgf rgg rgi rgk rgn rgo rgr rgs rib rie rif rig rii rik rin rio rir ris rkb rke rkf rkg rkk rko rks rnb rng rni rnn rno rnr rns rob roe rof rog roi rok ron roo ror ros rrb rrf rrg rri rrk rrn rrr rrs rsb rse rsf rsg rsi rsk rsn rso rsr rss sbb sbe sbf sbg sbi sbk sbn sbo sbr sbs se- seb see sef seg sei sek sen seo ser ses sfb sfe sff sfg sfi sfk sfn sfo sfr sfs sgb sge sgf sgg sgi sgk sgn sgo sgr sgs sib sie sif sig sii sik sin sio sir sis sk- skb ske skf skg ski skk sko skr sks snb sne snf sng sni snk snn sno snr sns sob soe sof sog soi sok son soo sor sos sr- srb sre srf srg sri srk srn sro srr srs ss- ssb sse ssf ssg ssi ssk ssn sso ssr sss