-er ddd dde ddn ddp ddr dds de- ded dee den dep der des dnd dne dnn dnp dnr dns dpd dpe dpn dpp dpr dps drd dre drn drp drr drs dsd dse dsn dsp dsr dss ed- edd ede edn edp edr eds eed eee een eep eer ees en- end ene enn enp enr ens ep- epd epe epn epp epr eps erd ere ern erp err ers es- esd ese esn esp esr ess ndd nde ndn ndp ndr nds ne- ned nee nen nep ner nes nne nnn nnp nns npd npe npn npp npr nps nrd nre nrn nrp nrr nrs nsd nse nsn nsp nsr nss p-p pdd pde pdn pdp pdr pds ped pee pen pep per pes pn- pnd pne pnn pnp pnr pns ppd ppe ppn ppp ppr pps prd pre prn prp prr prs ps- psd pse psn psp psr pss rdd rde rdn rdp rdr rds re- red ree ren rep rer res rnd rnn rnp rnr rns rpd rpe rpn rpp rpr rps rrd rrn rrp rrr rrs rsd rse rsn rsp rsr rss sdd sde sdn sdp sdr sds se- sed see sen sep ser ses snd sne snn snp snr sns spd spe spn spp spr sps sr- srd sre srn srp srr srs ss- ssd sse ssn ssp ssr sss