-er b-p bbb bbe bbf bbm bbn bbo bbp bbr be- beb bee bef bem ben beo bep ber bfb bfe bff bfm bfn bfo bfp bfr bmb bme bmf bmm bmn bmo bmp bmr bnb bne bnf bnn bno bnp bnr bob boe bof bom bon boo bop bor bpb bpe bpf bpm bpn bpo bpp bpr brb bre brf brm brn bro brp brr ebb ebe ebf ebm ebn ebo ebp ebr eeb eee eef eem een eeo eep eer ef- efb efe eff efm efo efp efr em- emb eme emf emm emn emo emp emr en- enb ene enf enm enn eno enp enr eo- eob eoe eof eom eon eoo eop eor ep- epb epe epf epm epn epo epp epr erb ere erf erm ern ero erp err fbb fbe fbf fbm fbn fbo fbp fbr feb fee fef fem fen feo fep fer ffe fff ffm ffn ffo ffp ffr fmb fme fmf fmm fmn fmo fmp fmr fnb fne fnf fnm fnn fnp fnr fob foe fof fom fon foo fop for fpb fpe fpm fpn fpo fpp fpr frb fre frf frm frn fro frp frr m-f m-o m-r mbb mbe mbf mbm mbo mbp mbr meb mee mef mem men meo mep mer mfb mfe mff mfm mfn mfo mfp mfr mmb mme mmf mmm mmn mmo mmp mmr mnb mne mnf mnm mnn mno mnp mnr mob moe mof mom mon moo mop mor mpb mpe mpf mpm mpn mpo mpp mpr mrb mre mrf mrm mrn mro mrp mrr nbb nbe nbf nbm nbn nbo nbp nbr ne- neb nee nef nem nen neo nep ner nfb nfe nff nfn nfo nfp nfr nmb nme nmm nmn nmo nmp nmr nnb nne nnf nnm nnn nno nnp no- nob noe nof nom non noo nop nor npb npe npf npm npn npo npp npr nrb nre nrf nrm nrn nro nrp nrr ob- obb obe obf obm obn obo obp obr oeb oee oef oem oen oeo oep oer of- ofb ofe off ofm ofn ofo ofp ofr om- omb ome omf omm omn omo omp omr on- onb one onf onn ono onp onr oo- oob oof oom oon ooo oop oor op- opb ope opf opm opn opo opp opr or- orb ore orf orm orn oro orp orr p-p pbb pbe pbf pbm pbn pbo pbp pbr peb pee pef pem pen peo pep per pfb pfe pff pfm pfn pfo pfp pfr pmb pme pmf pmm pmn pmo pmp pmr pn- pnb pne pnf pnm pnn pno pnp pnr pob poe pof pom pon poo pop por ppb ppe ppf ppm ppn ppo ppp ppr prb pre prf prm prn pro prp prr rbb rbe rbf rbm rbn rbo rbp rbr re- reb ree ref rem ren reo rep rer rfb rfe rff rfm rfn rfo rfp rfr rmb rme rmf rmm rmn rmo rmp rmr rnb rnm rnn rno rnp rnr rob roe rof rom ron roo rop ror rpb rpe rpf rpm rpn rpo rpp rpr rrb rrf rrm rrn rrp rrr