-er a-a a-b a-c a-t aaa aab aac aad aae aan aar aat ab- aba abb abc abd abe abn abr abt ac- aca acb acc acd ace acn acr act ad- ada adb adc add ade adn adr adt aea aeb aec aed aee aen aer aet an- ana anb anc and ane ann anr ant ar- ara arb arc ard are arn arr art at- ata atb atc atd ate atn atr att baa bab bac bad bae ban bar bat bba bbb bbc bbd bbe bbn bbr bbt bca bcb bcc bcd bce bcn bcr bct bda bdb bdc bdd bde bdr bdt be- bea beb bec bed bee ben ber bet bna bnb bnc bnd bne bnn bnr bnt bra brb brd bre brn brr brt bta btb btc btd bte btn btr btt c-- caa cab cac cad cae can car cat cba cbb cbc cbd cbe cbn cbr cbt cca ccb ccc ccd cce ccn ccr cct cda cdb cdc cdd cde cdn cdr cdt ce- cea ceb cec ced cee cen cer cet cn- cna cnb cnc cnd cne cnn cnr cnt cra crb crc crd cre crn crr crt cta ctb ctc ctd cte ctn ctr ctt daa dab dac dad dae dan dar dat dba dbb dbc dbd dbe dbn dbr dbt dca dcb dcc dcd dce dcn dcr dct dda ddb ddc ddd dde ddn ddr ddt de- dea deb dec ded dee den der det dna dnb dnc dnd dne dnn dnr dnt dra drb drc drd dre drn drr drt dta dtb dtc dtd dte dtn dtr dtt eaa eab eac ead eae ean ear eat eba ebb ebc ebd ebe ebn ebr ebt ec- eca ecb ecc ecd ece ecn ecr ect ed- eda edb edc edd ede edn edr edt eea eeb eec eed eee een eer eet en- ena enb enc end ene enn enr ent era erb erc erd ere ern err ert eta etb etc etd ete etn etr ett naa nab nac nad nae nan nar nat nba nbb nbc nbd nbe nbn nbr nbt nca ncb ncc ncd nce ncn ncr nct nda ndb ndc ndd nde ndn ndr ndt ne- nea neb nec ned nee nen ner net nna nnb nnc nne nnn nnt nra nrb nrc nrd nre nrn nrr nrt nta ntb ntc ntd nte ntn ntr ntt ra- raa rab rac rad rae ran rar rat rba rbb rbc rbd rbe rbn rbr rbt rca rcb rcc rcd rce rcn rcr rct rda rdb rdc rdd rde rdn rdr rdt re- rea reb rec red ree ren rer ret rna rnb rnc rnd rnn rnr rnt rra rrb rrc rrd rrn rrr rrt rta rtb rtc rtd rte rtn rtr rtt taa tab tac tad tae tan tar tat tba tbb tbc tbd tbe tbn tbr tbt tca tcb tcc tcd tce tcn tcr tct tda tdb tdc tdd tde tdn tdr tdt te- tea teb tec ted tee ten ter tet tna tnb tnc tnd tne tnn tnr tnt tra trb trc trd tre trn trr trt tta ttb ttc ttd tte ttn ttr ttt