-er a-a a-b aaa aab aad aae aan aar aas ab- aba abb abd abe abn abr abs ad- ada adb add ade adn adr ads aea aeb aed aee aen aer aes an- ana anb and ane ann anr ans ar- ara arb ard are arn arr ars as- asa asb asd ase asn asr ass baa bab bad bae ban bar bas bba bbb bbd bbe bbn bbr bbs bda bdb bdd bde bdr bds be- bea beb bed bee ben ber bes bna bnb bnd bne bnn bnr bns bra brb brd bre brn brr brs bsa bsb bsd bse bsn bsr bss daa dab dad dae dan dar das dba dbb dbd dbe dbn dbr dbs dda ddb ddd dde ddn ddr dds de- dea deb ded dee den der des dna dnb dnd dne dnn dnr dns dra drb drd dre drn drr drs dsa dsb dsd dse dsn dsr dss eaa eab ead eae ean ear eas eba ebb ebd ebe ebn ebr ebs ed- eda edb edd ede edn edr eds eea eeb eed eee een eer ees en- ena enb end ene enn enr ens era erb erd ere ern err ers es- esa esb esd ese esn esr ess naa nab nad nae nan nar nas nba nbb nbd nbe nbn nbr nbs nda ndb ndd nde ndn ndr nds ne- nea neb ned nee nen ner nes nna nnb nne nnn nns nra nrb nrd nre nrn nrr nrs nsa nsb nsd nse nsn nsr nss ra- raa rab rad rae ran rar ras rba rbb rbd rbe rbn rbr rbs rda rdb rdd rde rdn rdr rds re- rea reb red ree ren rer res rna rnb rnd rnn rnr rns rra rrb rrd rrn rrr rrs rsa rsb rsd rse rsn rsr rss saa sab sad sae san sar sas sba sbb sbd sbe sbn sbr sbs sda sdb sdd sde sdn sdr sds se- sea seb sed see sen ser ses sna snb snd sne snn snr sns sr- sra srb srd sre srn srr srs ss- ssa ssb ssd sse ssn ssr sss