(*start*)
Clear[f, A, B, x, n, k, s, rho];
f[x_] := Zeta[x];
A[n_, s_] :=
Sum[(-1)^(k - 1)*Binomial[n - 1, k - 1]/f[s + k/n - 1/n], {k, 1, n}]
B[n_, s_] :=
Sum[(-1)^(k - 1)*Binomial[n - 1, k - 1]/f[s + k/n], {k, 1, n}]
n = 30;
s = 14*I;
rho = s + 1/(1 - A[n, s]/B[n, s]);
N[%, n]
rho = -s + 1/(1 - B[n, s]/A[n, s]);
N[%, n]
Clear[f, A, B, x, n, k, s, rho];
Reduce[rho == s + 1/(1 - A/B) &&
s + 1/(1 - A/B) == Conjugate[-s + 1/(1 - B/A)], Re[rho], Complexes]
(*end*)
Clear[f, A, B, x, n, k, s, rho];
f[x_] := Zeta[x];
A[n_, s_] :=
Sum[(-1)^(k - 1)*Binomial[n - 1, k - 1]/f[s + k/n - 1/n], {k, 1, n}]
B[n_, s_] :=
Sum[(-1)^(k - 1)*Binomial[n - 1, k - 1]/f[s + k/n], {k, 1, n}]
n = 30;
s = 14*I;
rho = s + 1/(1 - A[n, s]/B[n, s]);
N[%, n]
rho = -s + 1/(1 - B[n, s]/A[n, s]);
N[%, n]
Clear[f, A, B, x, n, k, s, rho];
Reduce[rho == s + 1/(1 - A/B) &&
s + 1/(1 - A/B) == Conjugate[-s + 1/(1 - B/A)], Re[rho], Complexes]
(*end*)