The following problem is believed to be NP-Intermediate, i.e. it is in NP but neither in P nor NP-complete.
Exponentiating Polynomial Root Problem (EPRP)
Let $p(x)$ be a polynomial with $\deg(p) \geq 0$ with coefficients drawn from a finite field $GF(q)$ with $q$ a prime number, and $r$ a primitive root for that field. Determine the solutions of: $$p(x) = r^x $$ (or equivalently, the zeros of $p(x) - r^x$) where $r^x$ means exponentiating $r$.
Note that, when $\deg(p)=0$ (the polynomial is a constant), this problem reverts to the Discrete Logarithm Problem, which is believed to be NP-Intermediate as well.
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