-er bbb bbe bbi bbk bbn bbo bbr bbs bbt be- beb bee bei bek ben beo ber bes bet bi- bib bie bii bik bin bio bir bis bit bkb bke bkk bkn bko bkr bks bkt bnb bne bni bnk bnn bno bnr bns bnt bob boe boi bok bon boo bor bos bot brb bre bri brk brn bro brr brs brt bsb bse bsi bsk bsn bso bsr bss bst btb bte bti btk btn bto btr bts btt ebb ebe ebi ebk ebn ebo ebr ebs ebt eeb eee eek een eeo eer ees eet eib eie eii eik ein eio eir eis eit ekb eke eki eko ekr eks ekt en- enb ene eni enk enn eno enr ens ent eo- eob eoe eoi eok eon eoo eor eos eot erb ere eri erk ern ero err ers ert es- esb ese esi esk esn eso esr ess est etb ete eti etk etn eto etr ets ett ibb ibe ibi ibk ibn ibo ibr ibs ibt ie- iee iei iek ien ier ies iet iib iie iii iin iio iir iis iit ikb ike iki ikk iko ikr iks ikt in- inb ine ini ink inn ino inr ins int io- iob ioe ioi ion ioo ior ios iot ir- irb ire iri irk irn iro irr irs irt is- isb ise isi isk isn iso isr iss ist itb ite iti itk itn ito its itt k-t kbb kbe kbi kbk kbn kbo kbr kbs ke- keb kee kei kek ken keo ker kes ket kib kie kii kik kin kio kir kis kit kkb kke kki kkk kkn kkr kks kkt kn- kne kni knk knn kno knr knt kob koe koi kok kon koo kor kos kot kri krk krn kro krr krs krt ksb kse ksi ksk ksn kso ksr kss kst ktb kte ktk ktn kto ktr kts ktt n-i nbb nbe nbi nbk nbn nbo nbr nbs nbt ne- neb nee nei nek nen neo ner nes net nib nie nii nik nin nio nir nis nit nke nki nkk nkn nko nkr nks nkt nnb nne nni nnk nnn nno nns nnt no- nob noe noi nok non noo nor nos not nrb nre nri nrk nrn nro nrr nrs nrt nsb nse nsi nsk nsn nso nsr nss nst ntb nte nti ntk ntn nto ntr nts ntt o-i ob- obb obe obi obk obn obo obr obs obt oeb oee oei oen oeo oer oes oet oib oie oii oik oin oio oir ois oit okb oke oki okk oko okr oks on- onb one oni onk onn ono onr ons ont oo- oob ooi ook oon ooo oor oos oot or- orb ore ori ork orn oro orr ors ort os- osb ose osi osk osn oso osr oss ost ot- otb ote oti otk otn oto otr ots ott rbb rbe rbi rbk rbn rbo rbr rbs rbt re- reb ree rei rek ren reo rer res ret rib rie rii rik rin rio rir ris rit rkb rke rkk rko rks rkt rnb rni rnn rno rnr rns rnt rob roe roi rok ron roo ror ros rot rrb rri rrk rrn rrr rrs rrt rsb rse rsi rsk rsn rso rsr rss rst rtb rte rti rtk rtn rto rtr rts rtt sbb sbe sbi sbk sbn sbo sbr sbs sbt se- seb see sei sek sen seo ser ses set sib sie sii sik sin sio sir sis sit sk- skb ske ski skk sko skr sks skt snb sne sni snk snn sno snr sns snt sob soe soi sok son soo sor sos sot sr- srb sre sri srk srn sro srr srs srt ss- ssb sse ssi ssk ssn sso ssr sss sst stb ste sti stk stn sto str sts stt tbb tbe tbi tbk tbn tbo tbr tbs tbt te- teb tee tei tek ten teo ter tes tet tib tie tii tik tin tio tir tis tit tkb tke tkk tko tkr tks tkt tnb tne tni tnk tnn tno tnr tns tnt to- tob toe toi tok ton too tor tos tot trb tre tri trk trn tro trr trs trt tsb tse tsi tsk tsn tso tsr tss tst ttb tte tti ttk ttn tto ttr tts ttt