-er bbb bbe bbg bbi bbk bbn bbo bbr bbs be- beb bee beg bei bek ben beo ber bes bgb bge bgg bgi bgk bgn bgo bgr bgs bi- bib bie big bii bik bin bio bir bis bkb bke bkg bkk bkn bko bkr bks bnb bne bng bni bnk bnn bno bnr bns bob boe bog boi bok bon boo bor bos brb bre brg bri brk brn bro brr brs bsb bse bsg bsi bsk bsn bso bsr bss ebb ebe ebg ebi ebk ebn ebo ebr ebs eeb eee eeg eek een eeo eer ees egb ege egg egi egn ego egr egs eib eie eig eii eik ein eio eir eis ekb eke ekg eki eko ekr eks en- enb ene eng eni enk enn eno enr ens eo- eob eoe eog eoi eok eon eoo eor eos erb ere erg eri erk ern ero err ers es- esb ese esg esi esk esn eso esr ess gbe gbg gbi gbk gbn gbo gbr gbs ge- geb gee geg gei gek gen geo ger ges ggb ggg ggi ggn ggo ggr ggs gib gie gig gii gik gin gio gir gis gkb gkn gko gks gnb gne gni gnn gno gnr gns gob goe gog goi gok gon goo gor gos grb gre grg gri grk grn gro grr grs gsb gse gsg gsi gsk gsn gso gsr gss ibb ibe ibg ibi ibk ibn ibo ibr ibs ie- iee ieg iei iek ien ier ies igb ige igg igi igk ign igo igr igs iib iie iii iin iio iir iis ikb ike iki ikk iko ikr iks in- inb ine ing ini ink inn ino inr ins io- iob ioe iog ioi ion ioo ior ios ir- irb ire irg iri irk irn iro irr irs is- isb ise isg isi isk isn iso isr iss kbb kbe kbi kbk kbn kbo kbr kbs ke- keb kee keg kei kek ken keo ker kes kgb kgi kgo kgs kib kie kig kii kik kin kio kir kis kkb kke kki kkk kkn kkr kks kn- kne kng kni knk knn kno knr kob koe kog koi kok kon koo kor kos krg kri krk krn kro krr krs ksb kse ksg ksi ksk ksn kso ksr kss n-i nbb nbe nbg nbi nbk nbn nbo nbr nbs ne- neb nee neg nei nek nen neo ner nes ngb nge ngg ngi ngk ngn ngo ngs nib nie nig nii nik nin nio nir nis nke nki nkk nkn nko nkr nks nnb nne nng nni nnk nnn nno nns no- nob noe nog noi nok non noo nor nos nrb nre nrg nri nrk nrn nro nrr nrs nsb nse nsg nsi nsk nsn nso nsr nss o-i ob- obb obe obg obi obk obn obo obr obs oeb oee oeg oei oen oeo oer oes oge ogg ogi ogn ogo ogs oib oie oii oik oin oio oir ois okb oke okg oki okk oko okr oks on- onb one ong oni onk onn ono onr ons oo- oob oog ooi ook oon ooo oor oos or- orb ore org ori ork orn oro orr ors os- osb ose osg osi osk osn oso osr oss rbb rbe rbg rbi rbk rbn rbo rbr rbs re- reb ree reg rei rek ren reo rer res rgb rge rgg rgi rgk rgn rgo rgr rgs rib rie rig rii rik rin rio rir ris rkb rke rkg rkk rko rks rnb rng rni rnn rno rnr rns rob roe rog roi rok ron roo ror ros rrb rrg rri rrk rrn rrr rrs rsb rse rsg rsi rsk rsn rso rsr rss sbb sbe sbg sbi sbk sbn sbo sbr sbs se- seb see seg sei sek sen seo ser ses sgb sge sgg sgi sgk sgn sgo sgr sgs sib sie sig sii sik sin sio sir sis sk- skb ske skg ski skk sko skr sks snb sne sng sni snk snn sno snr sns sob soe sog soi sok son soo sor sos sr- srb sre srg sri srk srn sro srr srs ss- ssb sse ssg ssi ssk ssn sso ssr sss