F[n_, t_]  :=  
      Gamma[t + 
            1, (2*π*
                n)/((Sqrt[Cond]))]*(((((Sqrt[Cond])/(2*π*n))))^(t + 1))

Λ[
        s_]  :=  (∑_(n = 1)^100) 
            an[[n]]*(F[n, s - 1] + F[n, 1 - s])

an := {1, -2, -1, 2, 1, 2, -2, 0, -2, -2, 
        1, -2, 4, 4, -1, -4, -2, 4, 0, 2, 2, -2, -1, 
        0, -4, -8, 5, -4, 0, 2, 7, 8, -1, 4, -2, -4, 
        3, 0, -4, 0, -8, -4, -6, 2, -2, 2, 8, 4, -3, 
        8, 2, 8, -6, -10, 1, 0, 0, 0, 5, -2, 12, -14, 
        4, -8, 4, 2, -7, -4, 1, 4, -3, 0, 4, -6, 4, 
        0, -2, 8, -10, -4, 1, 16, -6, 4, -2, 12, 0, 0, 
        15, 4, -8, -2, -7, -16, 0, -8, -7, 
        6, -2, -8, 2, -4, -16, 0, 2, 12, 18, 10, 
        10, -2, -3, 8, 9, 0, -1, 0, -8, -10, 4, 0, 
        1, -24, 8, 14, -9, -8, 8, 0, 6, -8, -18, -2, 
        0, 14, 5, 0, -7, -2, 10, -4, -8, 6, 4, 8, 0, -8, 
        3, 6, -10, -8, 2, 0, 4, 4, 7, -8, -7, 20, 6, 8, 
        2, -2, 4, -16, -1, 12, -12, 0, 3, 4, 
        0, -12, -6, 0, 8, -4, -5, -30, -15, -4, 
        7, 16, -12, 0, 3, 14, -2, 16, -10, 0, 17, 8, 4, 
        14, -4, -6, -2, 4, 0, 0, 7, -4, 0, 4, -8, 32, 
        2, -16, 0, -4, 12, -12, 3, -36, -6, 
        0, -14, -20, -4, 2, -8, 6, 19, -16, 8, -18, 
        18, 0, 15, 2, 2, 0, 24, 16, 8, 10, 10, -8, -30, 
        4, -8, -2, -16, 24, -3, -16, 0, 0, 6, 
        18, -23, 8, -1, -16, 2, 16, -2, -12, -6, 8, 
        0, 36, 14, 0, -6, 0, -15, -14, 10, -10, -28, 8, 
        8, 14, -4, 2, -2, -20, -14, 0, -18, 16, 
        4, -6, 0, -8, 16, -16, -13, 0, 7, 8, 24, -6, 5, 
        0, 5, 20, -4, 8, 12, -4, -2, 0, 12, -8, 8, -4, 
        16, -14, 12, 0, -1, 14, 4, -20, 13, -12, 
        0, -8, -18, -4, 0, 2, -16, -8, -10, 
        0, -16, 2, 7, -12, -6, 
        24, -7, -8, -22, -6, -9, -4, 7, 0, 20, 0, 1, 
        12, 28, 0, 30, -16, 20, 8, -21, 10, -3, 30, -4, 
        30, -20, 0, -19, -14, -1, -16, 4, 24, -17, 4, 
        16, -6, 12, -14, -26, 4, 9, 0, 0, 20, -5, 
        0, -8, -34, -1, 0, -2, -8, 12, -14, -15, 
        8, 2, 0, 18, 4, -10, -4, -2, 0, 0, 16, 2, -14, 28, 4, 
        1, 0, 3, 0, -30, 16, 7, -32, -10, -4, -6, 
        32, -10, 0, 20, 4, 22, -24, -16, 0, 8, -6, -24, 
        36, -4, 12, -18, -20, -11, 28, 0, 20, 0, 8, 40, 0, 6, 
        16, -11, -6, 15, -38, 10, 16, 35, -16, -8, 
        18, -2, -36, -8, 0, -12, -30, -10, -2, 
        12, -4, -11, 0, -7, -48, -27, -16, 
        14, -16, 7, 0, -6, -20, 0, 8, 12, 60, 20, -8, 12, 
        16, -2, 2, -7, 32, 23, 0, -4, 6, -8, 16, 0, 
        0, -2, -28, 6, -12, 20, -18}

Cond := 11

Λ[1] // N

Λ[I] // N

\(\(Plot3D[
        Arg[Λ[x + I*y]], {x, \(-0.75\), 
          1.25}, {y, \(-0.75\), 1.25}, PlotPoints -> \ 20, 
        AxesLabel -> {"X", "Y", "|Λ|"}];\)\)

F[50, 0.1*I + 1] // N