Analytic continuation of sums of Hypergeometric $_3F_2$ function pairs

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While investigating the relationship

$$\Gamma\left[f,s\right]\zeta(s)=\Gamma\left[\hat{f},1-s\right] \zeta(1-s)\tag{1}$$

where $\Gamma\left[f,s\right]$ denotes the Mellin transform

$$\Gamma\left[f,s\right]=\int\limits_{-\infty}^\infty f(|x|)\, |x|^{s-1}\, dx=2 \int\limits_{-\infty}^\infty f(x)\, x^{s-1}\, dx\tag{2}$$

and $\hat{f}$ denotes the Fourier transform

$$\hat{f}(w)=\mathcal{F}_x[f(|x|)](w)=\int\limits_{-\infty }^{\infty} f(|x|)\, e^{-i 2 \pi w x} \, dx\tag{3}$$

for the functions

$$f_{1,r}(x)=2 \sqrt{r x}\, K_1\left(2\, \sqrt{r x}\right)\tag{4}$$

and

$$f_{2,r}(x)=-2 r x\, K_2\left(2\, \sqrt{r x}\right)\tag{5}$$

where $K_1(x)$ and $K_2(x)$ are modified bessel functions of the second kind, I discovered the analytic continuations

$$\frac{_3F_2\left(\frac{s}{2}+1,\frac{s}{2}+1,\frac{s}{2}+\frac{3}{2};\frac{3}{2},\frac{s}{2}+2;1\right)}{s+2}+\frac{_3F_2\left(\frac{s}{2}+\frac{1}{2},\frac{s}{2}+\frac{1}{2},\frac{s}{2}+1;\frac{1}{2},\frac{s}{2}+\frac{3}{2};1\right)}{(s+1)^2}=-\frac{\pi \csc (\pi s)}{s+1},\ \Re(s)<0\tag{6}$$

and

$$_3F_2\left(\frac{1}{2},\frac{s}{2}+\frac{3}{2},\frac{s}{2}+2;\frac{3}{2},\frac{3}{2};1\right)+\frac{_3F_2\left(\frac{s}{2}+\frac{3}{2},\frac{s}{2}+\frac{3}{2},\frac{s}{2}+2;\frac{3}{2},\frac{s}{2}+\frac{5}{2};1\right)}{s+3}=\frac{\pi \tan \left(\frac{\pi s}{2}\right)}{2 s+4},\ \Re(s)<-1\tag{7}$$

which are illustrated in Figures (1) and (2) below.


Question (1): Are the two analytic continuations defined in formulas (6) and (7) above two specific examples of a more general class of analytic continuations and if so, is there a formula for this generalization?

Question (2): Are there any other known analytic continuations related to the Hypergeometric $_3F_2$ function?


Figure (1) below illustrates the left-side of formula (6) in orange overlaid on the right-side of formula (6) in blue.

Illustration of left and right sides of formula (6) in orange and blue

Figure (1): Illustration of left and right sides of formula (6) in orange and blue


Figure (2) below illustrates the left-side of formula (7) in orange overlaid on the right-side of formula (7) in blue.

Illustration of left and right sides of formula (7) in orange and blue

Figure (2): Illustration of left and right sides of formula (7) in orange and blue


The relationship illustrated in formula (1) above is valid for any Schwartz function $f$, but it always simplifies to the Riemann zeta functional equation

$$\zeta(s)=\frac{\Gamma(\hat{f},1-s)}{\Gamma(f,s)}\,\zeta(1-s)=2^s\, \pi^{s-1}\, \sin\left(\frac{\pi s}{2}\right)\, \Gamma(1-s)\,\zeta(1-s)\tag{8}.$$


It also works with (at least some) distributions and non-Schwartz functions where perhaps the optimal choice is $f(x)=\delta(x-1)$ in which case

$$\hat{f}(w)=\mathcal{F}_x[f(|x|)](w)=2 \cos (2 \pi w)\tag{9}$$

and $\Gamma(f,s)=2$.