-er a-a a-b a-c a-t aaa aab aac aae aam aan aar aas aat ab- aba abb abc abe abm abn abr abs abt ac- aca acb acc ace acm acn acr acs act aea aeb aec aee aem aen aer aes aet ama amb amc ame amm amn amr ams amt an- ana anb anc ane anm ann anr ans ant ar- ara arb arc are arm arn arr ars art as- asa asb asc ase asm asn asr ass ast at- ata atb atc ate atm atn atr ats att baa bab bac bae bam ban bar bas bat bba bbb bbc bbe bbm bbn bbr bbs bbt bca bcb bcc bce bcm bcn bcr bcs bct be- bea beb bec bee bem ben ber bes bet bma bmb bmc bme bmm bmn bmr bms bmt bna bnb bnc bne bnn bnr bns bnt bra brb bre brm brn brr brs brt bsa bsb bsc bse bsm bsn bsr bss bst bta btb btc bte btm btn btr bts btt c-- caa cab cac cae cam can car cas cat cba cbb cbc cbe cbm cbn cbr cbs cbt cca ccb ccc cce ccm ccn ccr ccs cct ce- cea ceb cec cee cem cen cer ces cet cma cmb cmc cme cmm cmn cmr cms cmt cn- cna cnb cnc cne cnm cnn cnr cns cnt cra crb crc cre crm crn crr crs crt csa csb csc cse csm csn csr css cst cta ctb ctc cte ctm ctn ctr cts ctt eaa eab eac eae eam ean ear eas eat eba ebb ebc ebe ebm ebn ebr ebs ebt ec- eca ecb ecc ece ecm ecn ecr ecs ect eea eeb eec eee eem een eer ees eet em- ema emb emc eme emm emn emr ems emt en- ena enb enc ene enm enn enr ens ent era erb erc ere erm ern err ers ert es- esa esb esc ese esm esn esr ess est eta etb etc ete etm etn etr ets ett m-r maa mab mac mae mam man mar mas mat mba mbb mbc mbe mbm mbr mbs mbt mc- mca mcb mcc mce mcm mcn mcr mcs mct mea meb mec mee mem men mer mes met mma mmb mmc mme mmm mmn mmr mms mmt mna mnb mnc mne mnm mnn mnr mns mnt mra mrb mrc mre mrm mrn mrr mrs mrt msa msb msc mse msm msn msr mss mst mta mtb mtc mte mtm mtn mtr mts mtt naa nab nac nae nam nan nar nas nat nba nbb nbc nbe nbm nbn nbr nbs nbt nca ncb ncc nce ncm ncn ncr ncs nct ne- nea neb nec nee nem nen ner nes net nma nmb nmc nme nmm nmn nmr nms nmt nna nnb nnc nne nnm nnn nns nnt nra nrb nrc nre nrm nrn nrr nrs nrt nsa nsb nsc nse nsm nsn nsr nss nst nta ntb ntc nte ntm ntn ntr nts ntt ra- raa rab rac rae ram ran rar ras rat rba rbb rbc rbe rbm rbn rbr rbs rbt rca rcb rcc rce rcm rcn rcr rcs rct re- rea reb rec ree rem ren rer res ret rma rmb rmc rme rmm rmn rmr rms rmt rna rnb rnc rnm rnn rnr rns rnt rra rrb rrc rrm rrn rrr rrs rrt rsa rsb rsc rse rsm rsn rsr rss rst rta rtb rtc rte rtm rtn rtr rts rtt saa sab sac sae sam san sar sas sat sba sbb sbc sbe sbm sbn sbr sbs sbt sca scb scc sce scm scn scr scs sct se- sea seb sec see sem sen ser ses set sma smb smc sme smm smn smr sms smt sna snb snc sne snm snn snr sns snt sr- sra srb src sre srm srn srr srs srt ss- ssa ssb ssc sse ssm ssn ssr sss sst sta stb stc ste stm stn str sts stt taa tab tac tae tam tan tar tas tat tba tbb tbc tbe tbm tbn tbr tbs tbt tca tcb tcc tce tcm tcn tcr tcs tct te- tea teb tec tee tem ten ter tes tet tma tmb tmc tme tmm tmn tmr tms tmt tna tnb tnc tne tnm tnn tnr tns tnt tra trb trc tre trm trn trr trs trt tsa tsb tsc tse tsm tsn tsr tss tst tta ttb ttc tte ttm ttn ttr tts ttt