-er a-a a-c aaa aac aae aam aao aap aar aax ac- aca acc ace acm aco acp acr acx aea aec aee aem aeo aep aer aex ama amc ame amm amo amp amr amx aoa aoc aoe aom aoo aop aor aox ap- apa apc ape apm apo app apr apx ar- ara arc are arm aro arp arr arx ax- axa axe axm axo axp axr axx c-- caa cac cae cam cao cap car cax cca ccc cce ccm cco ccp ccr ccx ce- cea cec cee cem ceo cep cer cex cma cmc cme cmm cmo cmp cmr cmx co- coa coc coe com coo cop cor cox cpa cpc cpe cpm cpo cpp cpr cpx cra crc cre crm cro crp crr crx cxc cxo cxp cxr cxx eaa eac eae eam eao eap ear eax ec- eca ecc ece ecm eco ecr ecx eea eec eee eem eeo eep eer eex em- ema emc eme emm emo emp emr emx eo- eoa eoc eoe eom eoo eop eor ep- epa epc epe epm epo epp epr epx era erc ere erm ero erp err ex- exa exc exe exo exp exr exx m-o m-r maa mac mae mam mao map mar max mc- mca mcc mce mcm mco mcp mcr mcx mea mec mee mem meo mep mer mex mma mmc mme mmm mmo mmp mmr mmx moa moc moe mom moo mop mor mox mpa mpc mpe mpm mpo mpp mpr mpx mra mrc mre mrm mro mrp mrr mrx mxa mxc mxp mxr oaa oac oae oam oao oap oar oax oc- oca occ ocm oco ocp ocr ocx oea oec oee oem oeo oep oer oex om- oma omc ome omm omo omp omr omx oo- ooa ooc oom ooo oop oor oox op- opa opc ope opm opo opp opr opx or- ora orc ore orm oro orp orr orx ox- oxa oxc oxo oxx p-p paa pac pae pam pao pap par pax pca pcc pce pcm pco pcp pcr pcx pea pec pee pem peo pep per pex pma pmc pme pmm pmo pmp pmr pmx poa poc poe pom poo pop por pox ppa ppc ppe ppm ppo ppp ppr ppx pra prc pre prm pro prp prr prx pxc pxe pxm pxr ra- raa rac rae ram rao rap rar rax rca rcc rce rcm rco rcp rcr rcx re- rea rec ree rem reo rep rer rex rma rmc rme rmm rmo rmp rmr rmx roa roc roe rom roo rop ror rox rpa rpc rpe rpm rpo rpp rpr rpx rra rrc rrm rrp rrr rxp rxr xaa xac xam xap xar xcp xcr xcx xee xem xep xer xex xma xmc xmm xmo xmp xmr xmx xoa xoc xom xoo xop xor xox xpa xpc xpe xpm xpo xpp xrc xrx xxo xxp xxx