-er a-a a-b a-c aaa aab aac aad aae aag aan aar ab- aba abb abc abd abe abg abn abr ac- aca acb acc acd ace acg acn acr ad- ada adb adc add ade adg adn adr aea aeb aec aed aee aeg aen aer ag- aga agb agc agd age agg agn agr an- ana anb anc and ane ang ann anr ar- ara arb arc ard are arg arn arr baa bab bac bad bae bag ban bar bba bbb bbc bbd bbe bbg bbn bbr bca bcb bcc bcd bce bcg bcn bcr bda bdb bdc bdd bde bdg bdr be- bea beb bec bed bee beg ben ber bga bgb bgc bgd bge bgg bgn bgr bna bnb bnc bnd bne bng bnn bnr bra brb brd bre brg brn brr c-- caa cab cac cad cae cag can car cba cbb cbc cbd cbe cbg cbn cbr cca ccb ccc ccd cce ccg ccn ccr cda cdb cdc cdd cde cdg cdn cdr ce- cea ceb cec ced cee ceg cen cer cga cgb cgc cgd cge cgg cgn cgr cn- cna cnb cnc cnd cne cng cnn cnr cra crb crc crd cre crg crn crr daa dab dac dad dae dag dan dar dba dbb dbc dbd dbe dbg dbn dbr dca dcb dcc dcd dce dcg dcn dcr dda ddb ddc ddd dde ddg ddn ddr de- dea deb dec ded dee deg den der dga dgc dgd dge dgg dgn dgr dna dnb dnc dnd dne dng dnn dnr dra drb drc drd dre drg drn drr eaa eab eac ead eae eag ean ear eba ebb ebc ebd ebe ebg ebn ebr ec- eca ecb ecc ecd ece ecg ecn ecr ed- eda edb edc edd ede edg edn edr eea eeb eec eed eee eeg een eer ega egb egc egd ege egg egn egr en- ena enb enc end ene eng enn enr era erb erc erd ere erg ern err g-d gaa gab gac gad gae gag gan gar gba gbc gbd gbe gbg gbn gbr gca gcb gcc gcd gce gcg gcn gcr gda gdb gdc gdd gde gdn gdr ge- gea geb gec ged gee geg gen ger gga ggb ggc ggd ggg ggn ggr gna gnb gnc gnd gne gnn gnr gra grb grc grd gre grg grn grr naa nab nac nad nae nag nan nar nba nbb nbc nbd nbe nbg nbn nbr nca ncb ncc ncd nce ncg ncn ncr nda ndb ndc ndd nde ndg ndn ndr ne- nea neb nec ned nee neg nen ner nga ngb ngc ngd nge ngg ngn nna nnb nnc nne nng nnn nra nrb nrc nrd nre nrg nrn nrr ra- raa rab rac rad rae rag ran rar rba rbb rbc rbd rbe rbg rbn rbr rca rcb rcc rcd rce rcg rcn rcr rda rdb rdc rdd rde rdg rdn rdr re- rea reb rec red ree reg ren rer rga rgb rgc rgd rge rgg rgn rgr rna rnb rnc rnd rng rnn rnr rra rrb rrc rrd rrg rrn rrr