-er ddd dde ddi ddn ddr ddx de- ded dee dei den der dex di- did die dii din dir dix dnd dne dni dnn dnr drd dre dri drn drr drx dxd dxi dxn dxr dxx ed- edd ede edi edn edr edx eed eee een eer eex eid eie eii ein eir eix en- end ene eni enn enr erd ere eri ern err ex- exd exe exi exr exx i-d idd ide idi idn idr idx ie- ied iee iei ien ier iex iid iie iii iin iir iix in- ind ine ini inn inr inx ir- ird ire iri irn irr irx ixe ixi ixn n-i ndd nde ndi ndn ndr ne- ned nee nei nen ner nex nid nie nii nin nir nix nne nni nnn nrd nre nri nrn nrr nrx nxd rdd rde rdi rdn rdr rdx re- red ree rei ren rer rex rid rie rii rin rir rix rnd rni rnn rnr rrd rri rrn rrr rxr xde xdi xdr xed xee xen xer xex xie xii xin xix xrd xrx xxi xxx