-er ddd dde ddi ddn ddp ddr ddx de- ded dee dei den dep der dex di- did die dii din dip dir dix dnd dne dni dnn dnp dnr dpd dpe dpi dpn dpp dpr drd dre dri drn drp drr drx dxd dxi dxn dxp dxr dxx ed- edd ede edi edn edp edr edx eed eee een eep eer eex eid eie eii ein eip eir eix en- end ene eni enn enp enr ep- epd epe epi epn epp epr epx erd ere eri ern erp err ex- exd exe exi exp exr exx i-d idd ide idi idn idp idr idx ie- ied iee iei ien iep ier iex iid iie iii iin iip iir iix in- ind ine ini inn inp inr inx ipd ipe ipi ipn ipp ipr ipx ir- ird ire iri irn irp irr irx ixe ixi ixn n-i ndd nde ndi ndn ndp ndr ne- ned nee nei nen nep ner nex nid nie nii nin nip nir nix nne nni nnn nnp npd npe npi npn npp npr nrd nre nri nrn nrp nrr nrx nxd p-p pdd pde pdi pdn pdp pdr pdx ped pee pei pen pep per pex pid pie pii pin pip pir pix pn- pnd pne pni pnn pnp pnr pnx ppd ppe ppi ppn ppp ppr ppx prd pre pri prn prp prr prx pxe pxr rdd rde rdi rdn rdp rdr rdx re- red ree rei ren rep rer rex rid rie rii rin rip rir rix rnd rni rnn rnp rnr rpd rpe rpi rpn rpp rpr rpx rrd rri rrn rrp rrr rxp rxr xde xdi xdr xed xee xen xep xer xex xie xii xin xix xpd xpe xpn xpp xrd xrx xxi xxp xxx