cond[wr_] := Module[
  {
   n = 7,
   s = 20,
   \[Eta] = 10^-3,
   \[Epsilon] = 0,
   t = 2.75
   },


  If[
   OddQ[n],

   L = (n - 1)/2;


   U = DiagonalMatrix[
     Flatten[{0, t, 0,
       Table[{0, 0, 0, t, 0, 0, 0, t}, {i, 1, L}]}], -3];

   HH = DiagonalMatrix[
      Flatten[{\[Epsilon], \[Epsilon], \[Epsilon], \[Epsilon], \
\[Epsilon], \[Epsilon],
        Table[{\[Epsilon], \[Epsilon], \[Epsilon], \[Epsilon], \
\[Epsilon], \[Epsilon], \[Epsilon], \[Epsilon]}, {i, 1, L}]}], 0] +
     DiagonalMatrix[
      Flatten[{t, t, t, t, t,
        Table[{0, t, t, t, 0, t, t, t}, {i, 1, L}]}], 1] +
     DiagonalMatrix[
      Flatten[{0, 0, 0, Table[{0, 0, 0, 0, t, 0, 0, 0}, {i, 1, L}]}],
      3] +
     DiagonalMatrix[
      Flatten[{0, 0, Table[{t, 0, 0, 0, 0, 0, 0, 0}, {i, 1, L}]}],
      4] + DiagonalMatrix[
      Flatten[{t, Table[{0, 0, 0, 0, 0, 0, 0, t}, {i, 1, L}]}], 5] +
     If[n == 1, 0,
      DiagonalMatrix[
       Flatten[Table[{0, 0, 0, t, 0, 0, 0, 0}, {i, 1, L}]], 6]
      ];

   Energy = (wr + I*\[Eta])*
     DiagonalMatrix[
      Flatten[{1, 1, 1, 1, 1, 1,
        Table[{1, 1, 1, 1, 1, 1, 1, 1}, {i, 1, L}]}], 0];

   ,
   L = n/2;


   U = DiagonalMatrix[
     Flatten[{0, t, 0, 0, 0, 0, t,
       Table[{0, 0, 0, t, 0, 0, 0, t}, {i, 1, L - 1}]}], -3];

   HH = DiagonalMatrix[
      Flatten[{\[Epsilon], \[Epsilon], \[Epsilon], \[Epsilon], \
\[Epsilon], \[Epsilon], \[Epsilon], \[Epsilon], \[Epsilon], \
\[Epsilon],
        Table[{\[Epsilon], \[Epsilon], \[Epsilon], \[Epsilon], \
\[Epsilon], \[Epsilon], \[Epsilon], \[Epsilon]}, {i, 1, L - 1}]}],
      0] + DiagonalMatrix[
      Flatten[{t, t, t, t, t, 0, t, t, t,
        Table[{0, t, t, t, 0, t, t, t}, {i, 1, L - 1}]}], 1] +

     DiagonalMatrix[
      Flatten[{0, 0, t, 0, 0, 0,
        Table[{0, 0, 0, 0, 0, 0, 0, 0}, {i, 1, L - 1}]}], 4] +

     DiagonalMatrix[
      Flatten[{0, 0, 0, 0, 0, 0, 0,
        Table[{t, 0, 0, 0, t, 0, 0, 0}, {i, 1, L - 1}]}], 3] +

     DiagonalMatrix[
      Flatten[{t, 0, 0, 0, 0,
        Table[{0, 0, 0, t, 0, 0, 0, t}, {i, 1, L - 1}]}], 5] +
     DiagonalMatrix[
      Flatten[{0, 0, 0, t,
        Table[{0, 0, 0, 0, 0, 0, 0, 0}, {i, 1, L - 1}]}], 6];

   Energy = (wr + I*\[Eta])*
     DiagonalMatrix[
      Flatten[{1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
        Table[{1, 1, 1, 1, 1, 1, 1, 1}, {i, 1, L - 1}]}], 0];

   ];

  H = ConjugateTranspose[HH] + HH;
  Subscript[a, 1] =
   ConjugateTranspose[U].Inverse[Energy - H].ConjugateTranspose[
     U];(*\[Gamma]*)
  \[Alpha] = ConjugateTranspose[U].Inverse[Energy - H].U;
  \[Beta] = U.Inverse[Energy - H].ConjugateTranspose[U];
  Subscript[b, 1] = U.Inverse[Energy - H].U;(*\[Lambda]*)
  Subscript[c, 1] = Subscript[d, 1] = 0;

  Subscript[AA, 1] =
   ConjugateTranspose[ConjugateTranspose[U]].Inverse[
     Energy - H].ConjugateTranspose[
     ConjugateTranspose[U]];(*\[Gamma]*)
  \[CapitalAlpha] =
   ConjugateTranspose[ConjugateTranspose[U]].Inverse[
     Energy - H].ConjugateTranspose[U];
  \[CapitalBeta] =
   ConjugateTranspose[U].Inverse[Energy - H].ConjugateTranspose[
     ConjugateTranspose[U]];
  Subscript[BB, 1] =
   ConjugateTranspose[U].Inverse[Energy - H].ConjugateTranspose[
     U];(*\[Lambda]*)
  Subscript[CC, 1] = Subscript[DD, 1] = 0;


  Table[
   Subscript[c, i] =
    Subscript[c, i - 1] +
     Subscript[a,
      i - 1].Inverse[
       Energy - H - \[Alpha] - \[Beta] - Subscript[c,
        i - 1]].Subscript[b, i - 1] +
     Subscript[b,
      i - 1].Inverse[
       Energy - H - \[Alpha] - \[Beta] - Subscript[c,
        i - 1]].Subscript[a, i - 1];

   Subscript[a, i] =
    Subscript[a,
     i - 1].Inverse[
      Energy - H - \[Alpha] - \[Beta] - Subscript[c,
       i - 1]].Subscript[a, i - 1];

   Subscript[b, i] =
    Subscript[b,
     i - 1].Inverse[
      Energy - H - \[Alpha] - \[Beta] - Subscript[c,
       i - 1]].Subscript[b, i - 1];
   Subscript[d, i] =
    Subscript[d, i - 1] +
     Subscript[b,
      i - 1].Inverse[
       Energy - H - \[Alpha] - \[Beta] - Subscript[c,
        i - 1]].Subscript[a, i - 1];
   G0 = Inverse[Energy - H - \[Beta] - Subscript[d, i]];

   Subscript[CC, i] =
    Subscript[CC, i - 1] +
     Subscript[AA,
      i - 1].Inverse[
       Energy - H - \[CapitalAlpha] - \[CapitalBeta] - Subscript[CC,
        i - 1]].Subscript[BB, i - 1] +
     Subscript[BB,
      i - 1].Inverse[
       Energy - H - \[CapitalAlpha] - \[CapitalBeta] - Subscript[CC,
        i - 1]].Subscript[AA, i - 1];

   Subscript[BB, i] =
    Subscript[BB,
     i - 1].Inverse[
      Energy - H - \[CapitalAlpha] - \[CapitalBeta] - Subscript[CC,
       i - 1]].Subscript[BB, i - 1];

   Subscript[AA, i] =
    Subscript[AA,
     i - 1].Inverse[
      Energy - H - \[CapitalAlpha] - \[CapitalBeta] - Subscript[CC,
       i - 1]].Subscript[AA, i - 1];

   Subscript[DD, i] =
    Subscript[DD, i - 1] +
     Subscript[BB,
      i - 1].Inverse[
       Energy - H - \[CapitalAlpha] - \[CapitalBeta] - Subscript[CC,
        i - 1]].Subscript[AA, i - 1];

   G2 = Inverse[Energy - H - \[CapitalBeta] - Subscript[DD, i]];


   , {i, 2, s}];


  (*---------------------------------------------------------------------*)
\


  SIGMAL = U.G0.ConjugateTranspose[U];
  SIGMAR =
   ConjugateTranspose[U].G2.ConjugateTranspose[ConjugateTranspose[U]];
  (*G11=Inverse[E1-H1-V10.G0.V01-V12.G0.V21];
  Usando parte central 3X3*)

  G11 = Inverse[Energy - H - SIGMAL - SIGMAR];

  \[CapitalGamma]L = I*(SIGMAL - ConjugateTranspose[SIGMAL]);
  \[CapitalGamma]R = I*(SIGMAR - ConjugateTranspose[SIGMAR]);


  Tra = Tr[\[CapitalGamma]L.G11.\[CapitalGamma]R.ConjugateTranspose[
      G11]];
  (*-----------------------------Returning---------------------------------\
---*)


  Re[Tra]  ]