Given $x_{n-1}=1$ solve recurrence $x_{j}-x_{j-1}=x_{j-1}-x_{j-2}$

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Solve all $n$ variables $x_0,...,x_{n-1}$ given

$$ x_{j}-x_{j-1}=x_{j-1}-x_{j-2},\quad j\ge 2\\ x_{1}-x_{0}=x_{0}\\ x_{n-1}=1 $$

this looks like recurrence but the initial condition is at $n-1$ rather than $0$, also there's only one such condition, so I don't think traditional characteristic root method of guessing the solution is of the form $r^j$ would work.

This maybe irrelavant but actually $\pi(x_j-x_{j-1})$ is the number of points on a unit circle with distance to origin in the range of $(x_{j-1}^{1/2},x_{j}^{1/2}]$ where we've $n$-partitioned $(0,1]$ into $(0,x_{0}^{1/2}],...,(x_{n-1}^{1/2},1]$. Above is really trying to associate each partition to same number of points.

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As dxiv points out, the differences between consecutive terms is constant. The second equation says this constant is $x_0$. Therefore $x_j = (j+1) x_0$, and, in particular, $1 = x_{n-1} = n x_0$. Therefore $x_0 = 1/n$ and $x_j = (j+1)/n$.