-er b-p bbb bbe bbi bbk bbn bbp bbr bbs be- beb bee bei bek ben bep ber bes bi- bib bie bii bik bin bip bir bis bkb bke bkk bkn bkp bkr bks bnb bne bni bnk bnn bnp bnr bns bpb bpe bpi bpn bpp bpr bps brb bre bri brk brn brp brr brs bsb bse bsi bsk bsn bsp bsr bss ebb ebe ebi ebk ebn ebp ebr ebs eeb eee eek een eep eer ees eib eie eii eik ein eip eir eis ekb eke eki ekp ekr eks en- enb ene eni enk enn enp enr ens ep- epb epe epi epn epp epr eps erb ere eri erk ern erp err ers es- esb ese esi esk esn esp esr ess ibb ibe ibi ibk ibn ibp ibr ibs ie- iee iei iek ien iep ier ies iib iie iii iin iip iir iis ikb ike iki ikk ikr iks in- inb ine ini ink inn inp inr ins ipb ipe ipi ipn ipp ipr ips ir- irb ire iri irk irn irp irr irs is- isb ise isi isk isn isp isr iss kbb kbe kbi kbk kbn kbp kbr kbs ke- keb kee kei kek ken kep ker kes kib kie kii kik kin kip kir kis kkb kke kki kkk kkn kkp kkr kks kn- kne kni knk knn knp knr kpe kpi kpk kpn kpp kpr kps kri krk krn krp krr krs ksb kse ksi ksk ksn ksp ksr kss n-i nbb nbe nbi nbk nbn nbp nbr nbs ne- neb nee nei nek nen nep ner nes nib nie nii nik nin nip nir nis nke nki nkk nkn nkp nkr nks nnb nne nni nnk nnn nnp nns npb npe npi npn npp npr nps nrb nre nri nrk nrn nrp nrr nrs nsb nse nsi nsk nsn nsp nsr nss p-p pbb pbe pbi pbk pbn pbp pbr pbs peb pee pei pek pen pep per pes pib pie pii pik pin pip pir pis pkb pke pki pkn pkp pkr pks pn- pnb pne pni pnk pnn pnp pnr pns ppb ppe ppi ppk ppn ppp ppr pps prb pre pri prk prn prp prr prs ps- psb pse psi psk psn psp psr pss rbb rbe rbi rbk rbn rbp rbr rbs re- reb ree rei rek ren rep rer res rib rie rii rik rin rip rir ris rkb rke rkk rkp rks rnb rni rnn rnp rnr rns rpb rpe rpi rpk rpn rpp rpr rps rrb rri rrk rrn rrp rrr rrs rsb rse rsi rsk rsn rsp rsr rss sbb sbe sbi sbk sbn sbp sbr sbs se- seb see sei sek sen sep ser ses sib sie sii sik sin sip sir sis sk- skb ske ski skk skp skr sks snb sne sni snk snn snp snr sns spb spe spi spk spn spp spr sps sr- srb sre sri srk srn srp srr srs ss- ssb sse ssi ssk ssn ssp ssr sss