Which Prime Numbers Make $2p^3 + 4p^2 - 3p + 12$ a Fifth Power?

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The discussion focuses on identifying prime numbers \( p \) such that the expression \( 2p^3 + 4p^2 - 3p + 12 \) equals a fifth power of an integer. The problem is categorized as a Problem of the Week (POTW), indicating its mathematical significance. Participants are encouraged to explore the properties of prime numbers and polynomial equations to derive solutions. The lack of responses to previous POTWs highlights the challenge level of this problem.

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Here is this week's POTW:

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Find all prime numbers $p$ such that $2p^3+4p^2-3p+12$ is the fifth power of an integer.

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No one answered last two week's POTW. (Sadface) However, you can find the suggested solution as follows:
Denote $f(n)=2n^3+4n^2-3n+12$. The following table shows the remainders of $n^2,\,n^3,\,n^5$ and $f(n)$ upon division by 11:
\begin{equation*}
\begin{array}{c|c|c|c|c}
n & 0 & 1 & 2 &3 & 4 & 5 & 6 & 7 & 8 & 9 & 10 \\
\hline
n^2 & 0 & 1 & 4 & 9 & 9 & 3 & 3 & 5 & 9 & 1 & 1 \\
n^3 & 0 & 1 & 8 & 5 & 9 & 4 & 7 & 2 & 6 & 3 & 10 \\
n^5 & 0 & 1 & 10 & 1 & 1 & 1 & 10 & 10 & 10 & 1 & 10 \\
f(n) & 1 & 4 & 5 & 5 & 5 & 6 & 9 & 4 & 3 & 7 & 6 \\
\end{array}
\end{equation*}

As one can see from the table, the only remainders upon division by 11 that the fifth power of an arbitrary integer $n$ can give are 0, 1, and 10. On the other hand, integers of the form $f(n)$ give only remainders 1, 3, 4, 5, 6, 7, and 9 upon division by 11, whereby the remainder is 1 only if $n$ is divisible by 11. Consequently, $f(p)$ can be the fifth power of an integer only if $p$ is divisible by 11. As $p$ is prime, the only possibility is $p=11$. And indeed, $f(11)=2\cdot 11^3+4\cdot 11^2-3\cdot 11+12=3125=5^5$.
 

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