-er a-a a-b aaa aab aad aae aag aan aar ab- aba abb abd abe abg abn abr ad- ada adb add ade adg adn adr aea aeb aed aee aeg aen aer ag- aga agb agd age agg agn agr an- ana anb and ane ang ann anr ar- ara arb ard are arg arn arr baa bab bad bae bag ban bar bba bbb bbd bbe bbg bbn bbr bda bdb bdd bde bdg bdr be- bea beb bed bee beg ben ber bga bgb bgd bge bgg bgn bgr bna bnb bnd bne bng bnn bnr bra brb brd bre brg brn brr daa dab dad dae dag dan dar dba dbb dbd dbe dbg dbn dbr dda ddb ddd dde ddg ddn ddr de- dea deb ded dee deg den der dga dgd dge dgg dgn dgr dna dnb dnd dne dng dnn dnr dra drb drd dre drg drn drr eaa eab ead eae eag ean ear eba ebb ebd ebe ebg ebn ebr ed- eda edb edd ede edg edn edr eea eeb eed eee eeg een eer ega egb egd ege egg egn egr en- ena enb end ene eng enn enr era erb erd ere erg ern err g-d gaa gab gad gae gag gan gar gba gbd gbe gbg gbn gbr gda gdb gdd gde gdn gdr ge- gea geb ged gee geg gen ger gga ggb ggd ggg ggn ggr gna gnb gnd gne gnn gnr gra grb grd gre grg grn grr naa nab nad nae nag nan nar nba nbb nbd nbe nbg nbn nbr nda ndb ndd nde ndg ndn ndr ne- nea neb ned nee neg nen ner nga ngb ngd nge ngg ngn nna nnb nne nng nnn nra nrb nrd nre nrg nrn nrr ra- raa rab rad rae rag ran rar rba rbb rbd rbe rbg rbn rbr rda rdb rdd rde rdg rdn rdr re- rea reb red ree reg ren rer rga rgb rgd rge rgg rgn rgr rna rnb rnd rng rnn rnr rra rrb rrd rrg rrn rrr