-er a-a a-b a-c aaa aab aac aae aam aan aap aar ab- aba abb abc abe abm abn abp abr ac- aca acb acc ace acm acn acp acr aea aeb aec aee aem aen aep aer ama amb amc ame amm amn amp amr an- ana anb anc ane anm ann anp anr ap- apa apb apc ape apm apn app apr ar- ara arb arc are arm arn arp arr b-p baa bab bac bae bam ban bap bar bba bbb bbc bbe bbm bbn bbp bbr bca bcb bcc bce bcm bcn bcp bcr be- bea beb bec bee bem ben bep ber bma bmb bmc bme bmm bmn bmp bmr bna bnb bnc bne bnn bnp bnr bpa bpb bpc bpe bpm bpn bpp bpr bra brb bre brm brn brp brr c-- caa cab cac cae cam can cap car cba cbb cbc cbe cbm cbn cbp cbr cca ccb ccc cce ccm ccn ccp ccr ce- cea ceb cec cee cem cen cep cer cma cmb cmc cme cmm cmn cmp cmr cn- cna cnb cnc cne cnm cnn cnp cnr cpa cpb cpc cpe cpm cpn cpp cpr cra crb crc cre crm crn crp crr eaa eab eac eae eam ean eap ear eba ebb ebc ebe ebm ebn ebp ebr ec- eca ecb ecc ece ecm ecn ecr eea eeb eec eee eem een eep eer em- ema emb emc eme emm emn emp emr en- ena enb enc ene enm enn enp enr ep- epa epb epc epe epm epn epp epr era erb erc ere erm ern erp err m-r maa mab mac mae mam man map mar mba mbb mbc mbe mbm mbp mbr mc- mca mcb mcc mce mcm mcn mcp mcr mea meb mec mee mem men mep mer mma mmb mmc mme mmm mmn mmp mmr mna mnb mnc mne mnm mnn mnp mnr mpa mpb mpc mpe mpm mpn mpp mpr mra mrb mrc mre mrm mrn mrp mrr naa nab nac nae nam nan nap nar nba nbb nbc nbe nbm nbn nbp nbr nca ncb ncc nce ncm ncn ncp ncr ne- nea neb nec nee nem nen nep ner nma nmb nmc nme nmm nmn nmp nmr nna nnb nnc nne nnm nnn nnp npa npb npc npe npm npn npp npr nra nrb nrc nre nrm nrn nrp nrr p-p paa pab pac pae pam pan pap par pba pbb pbc pbe pbm pbn pbp pbr pca pcb pcc pce pcm pcn pcp pcr pea peb pec pee pem pen pep per pma pmb pmc pme pmm pmn pmp pmr pn- pna pnb pnc pne pnm pnn pnp pnr ppa ppb ppc ppe ppm ppn ppp ppr pra prb prc pre prm prn prp prr ra- raa rab rac rae ram ran rap rar rba rbb rbc rbe rbm rbn rbp rbr rca rcb rcc rce rcm rcn rcp rcr re- rea reb rec ree rem ren rep rer rma rmb rmc rme rmm rmn rmp rmr rna rnb rnc rnm rnn rnp rnr rpa rpb rpc rpe rpm rpn rpp rpr rra rrb rrc rrm rrn rrp rrr