A Bessel function inspired recurrent sum

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I came up upon the following recurrent sum.

$a\cdot (B_{n-1}\cdot e^{i\cdot k_0 \cdot z}+ B_{n+1}\cdot e^{-i\cdot k_0 \cdot z})=2 \cdot n \cdot B_n$

Where $a$ is complex , $k_0$ and $z$ are real, $n$ is an integer.

In the case where $z=0$ we get the standard Bessel recurrence summation, what happens for general real $z$?

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Following @metamorphy suggestion, the trick is the following. We will assume that the structure of the recurring term is the following

$B_n=B_0 \cdot e^{ink_0z}\cdot J_n(a)$

Plugging this solution into the equation we get

$a \cdot (B_0\cdot e^{i(n-1)k_0z}\cdot J_{n-1}(a) \cdot e^{ik_0z}+B_0\cdot e^{i(n+1)k_0z}\cdot J_{n+1}(a) \cdot e^{-ik_0z})=2\cdot n \cdot B_0 \cdot e^{ink_0z}\cdot J_n(a)$

This becomes

$(J_{n-1}(a) +J_{n+1}(a) )=\frac{2n}{a} \cdot J_n(a)$

which is the standard Bessel function recurrence sequence.