-er b-p bbb bbc bbe bbm bbo bbp bbr bbs bbt bcb bcc bce bcm bco bcp bcr bcs bct be- beb bec bee bem beo bep ber bes bet bmb bmc bme bmm bmo bmp bmr bms bmt bob boc boe bom boo bop bor bos bot bpb bpc bpe bpm bpo bpp bpr bps bpt brb bre brm bro brp brr brs brt bsb bsc bse bsm bso bsp bsr bss bst btb btc bte btm bto btp btr bts btt c-- cbb cbc cbe cbm cbo cbp cbr cbs cbt ccb ccc cce ccm cco ccp ccr ccs cct ce- ceb cec cee cem ceo cep cer ces cet cmb cmc cme cmm cmo cmp cmr cms cmt co- cob coc coe com coo cop cor cos cot cpb cpc cpe cpm cpo cpp cpr cps cpt crb crc cre crm cro crp crr crs crt csb csc cse csm cso csp csr css cst ctb ctc cte ctm cto ctp ctr cts ctt ebb ebc ebe ebm ebo ebp ebr ebs ebt ec- ecb ecc ece ecm eco ecr ecs ect eeb eec eee eem eeo eep eer ees eet em- emb emc eme emm emo emp emr ems emt eo- eob eoc eoe eom eoo eop eor eos eot ep- epb epc epe epm epo epp epr eps ept erb erc ere erm ero erp err ers ert es- esb esc ese esm eso esp esr ess est etb etc ete etm eto etp etr ets ett m-o m-r mbb mbc mbe mbm mbo mbp mbr mbs mbt mc- mcb mcc mce mcm mco mcp mcr mcs mct meb mec mee mem meo mep mer mes met mmb mmc mme mmm mmo mmp mmr mms mmt mob moc moe mom moo mop mor mos mot mpb mpc mpe mpm mpo mpp mpr mps mpt mrb mrc mre mrm mro mrp mrr mrs mrt msb msc mse msm mso msp msr mss mst mtb mtc mte mtm mto mtp mtr mts mtt ob- obb obc obe obm obo obp obr obs obt oc- ocb occ ocm oco ocp ocr ocs oct oeb oec oee oem oeo oep oer oes oet om- omb omc ome omm omo omp omr oms omt oo- oob ooc oom ooo oop oor oos oot op- opb opc ope opm opo opp opr ops opt or- orb orc ore orm oro orp orr ors ort os- osb osc ose osm oso osp osr oss ost ot- otb otc ote otm oto otp otr ots ott p-p pbb pbc pbe pbm pbo pbp pbr pbs pbt pcb pcc pce pcm pco pcp pcr pcs pct peb pec pee pem peo pep per pes pet pmb pmc pme pmm pmo pmp pmr pms pmt pob poc poe pom poo pop por pos pot ppb ppc ppe ppm ppo ppp ppr pps ppt prb prc pre prm pro prp prr prs prt ps- psb psc pse psm pso psp psr pss pst pt- ptb ptc pte ptm pto ptp ptr pts ptt rbb rbc rbe rbm rbo rbp rbr rbs rbt rcb rcc rce rcm rco rcp rcr rcs rct re- reb rec ree rem reo rep rer res ret rmb rmc rme rmm rmo rmp rmr rms rmt rob roc roe rom roo rop ror ros rot rpb rpc rpe rpm rpo rpp rpr rps rpt rrb rrc rrm rrp rrr rrs rrt rsb rsc rse rsm rso rsp rsr rss rst rtb rtc rte rtm rto rtp rtr rts rtt sbb sbc sbe sbm sbo sbp sbr sbs sbt scb scc sce scm sco scp scr scs sct se- seb sec see sem seo sep ser ses set smb smc sme smm smo smp smr sms smt sob soc soe som soo sop sor sos sot spb spc spe spm spo spp spr sps spt sr- srb src sre srm sro srp srr srs srt ss- ssb ssc sse ssm sso ssp ssr sss sst stb stc ste stm sto stp str sts stt tbb tbc tbe tbm tbo tbp tbr tbs tbt tcb tcc tce tcm tco tcp tcr tcs tct te- teb tec tee tem teo tep ter tes tet tmb tmc tme tmm tmo tmp tmr tms tmt to- tob toc toe tom too top tor tos tot tpb tpc tpe tpm tpo tpp tpr tps tpt trb trc tre trm tro trp trr trs trt tsb tsc tse tsm tso tsp tsr tss tst ttb ttc tte ttm tto ttp ttr tts ttt