-er a-a a-b a-t aaa aab aae aan aap aar aas aat ab- aba abb abe abn abp abr abs abt aea aeb aee aen aep aer aes aet an- ana anb ane ann anp anr ans ant ap- apa apb ape apn app apr aps apt ar- ara arb are arn arp arr ars art as- asa asb ase asn asp asr ass ast at- ata atb ate atn atp atr ats att b-p baa bab bae ban bap bar bas bat bba bbb bbe bbn bbp bbr bbs bbt be- bea beb bee ben bep ber bes bet bna bnb bne bnn bnp bnr bns bnt bpa bpb bpe bpn bpp bpr bps bpt bra brb bre brn brp brr brs brt bsa bsb bse bsn bsp bsr bss bst bta btb bte btn btp btr bts btt eaa eab eae ean eap ear eas eat eba ebb ebe ebn ebp ebr ebs ebt eea eeb eee een eep eer ees eet en- ena enb ene enn enp enr ens ent ep- epa epb epe epn epp epr eps ept era erb ere ern erp err ers ert es- esa esb ese esn esp esr ess est eta etb ete etn etp etr ets ett naa nab nae nan nap nar nas nat nba nbb nbe nbn nbp nbr nbs nbt ne- nea neb nee nen nep ner nes net nna nnb nne nnn nnp nns nnt npa npb npe npn npp npr nps npt nra nrb nre nrn nrp nrr nrs nrt nsa nsb nse nsn nsp nsr nss nst nta ntb nte ntn ntp ntr nts ntt p-p paa pab pae pan pap par pas pat pba pbb pbe pbn pbp pbr pbs pbt pea peb pee pen pep per pes pet pn- pna pnb pne pnn pnp pnr pns pnt ppa ppb ppe ppn ppp ppr pps ppt pra prb pre prn prp prr prs prt ps- psa psb pse psn psp psr pss pst pt- pta ptb pte ptn ptp ptr pts ptt ra- raa rab rae ran rap rar ras rat rba rbb rbe rbn rbp rbr rbs rbt re- rea reb ree ren rep rer res ret rna rnb rnn rnp rnr rns rnt rpa rpb rpe rpn rpp rpr rps rpt rra rrb rrn rrp rrr rrs rrt rsa rsb rse rsn rsp rsr rss rst rta rtb rte rtn rtp rtr rts rtt saa sab sae san sap sar sas sat sba sbb sbe sbn sbp sbr sbs sbt se- sea seb see sen sep ser ses set sna snb sne snn snp snr sns snt spa spb spe spn spp spr sps spt sr- sra srb sre srn srp srr srs srt ss- ssa ssb sse ssn ssp ssr sss sst sta stb ste stn stp str sts stt taa tab tae tan tap tar tas tat tba tbb tbe tbn tbp tbr tbs tbt te- tea teb tee ten tep ter tes tet tna tnb tne tnn tnp tnr tns tnt tpa tpb tpe tpn tpp tpr tps tpt tra trb tre trn trp trr trs trt tsa tsb tse tsn tsp tsr tss tst tta ttb tte ttn ttp ttr tts ttt