Alternative proof of irreducibility of a geometric series polynomial

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Prove, in $ \displaystyle \mathbb{Z} \left[ x \right]$, the irreducibility of

$ \displaystyle p + \sum_{k=1}^n x^k$

where $n>1$ and $p$ a prime number.

It is not too difficult to exploit the magnitude of the roots to create a contradiction under the assumption that the polynomial factors.

However, I am wondering if there are other means of proving the irreducibility of this polynomial, such as through Eisenstein's Criterion.