Recurrence Relations Calling Each Other

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I have n recurrence relations of the following form:

For $i=1$:

$v_1(t) = \frac{1}{2}v_1(t-1) + \frac{1}{2}v_2(t-1)$

for $1<i<n$:

$v_i(t) = \frac{1}{2}v_{i-1}(t-1) + \frac{1}{2}v_{i+1}(t-1)$

For $i=n$:

$v_n(t) = \frac{1}{2}v_{n-1}(t-1) + \frac{1}{2}v_n(t-1)$

Additionally, for all $i$:

$v_i(0) = x_i$, a variable representing an initial value.

Does anyone know how to solve this?

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$$ v_{i,t} = \frac{1}{2}\left(v_{i-1,t-1}+v_{i+1,t-1}\right) $$

Making $v_{i,t} = \alpha^i\beta^t$ and substituting we get

$$ \alpha + \alpha^{-1} = 2\beta\Rightarrow \alpha = \beta \pm \sqrt{\beta^2-1} $$

or

$$ v_{i,t} = C_1\alpha_1(\beta)^i\beta^t + C_2\alpha_2(\beta)^i\beta^t $$

etc.