Is 2017^4+4^{2017} a Prime Number?

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Discussion Overview

The discussion centers around the question of whether the expression \(2017^4 + 4^{2017}\) is a prime number. Participants explore this mathematical inquiry without reaching a definitive conclusion.

Discussion Character

  • Mathematical reasoning

Main Points Raised

  • Some participants inquire about the primality of \(2017^4 + 4^{2017}\), repeating the question without providing additional context or solutions.
  • One participant mentions posting their solution despite another participant's earlier contribution, indicating a possible overlap in approaches or reasoning.

Areas of Agreement / Disagreement

The discussion does not show clear agreement or disagreement, as participants primarily restate the question without presenting differing views or solutions.

Contextual Notes

There are no detailed mathematical steps or assumptions provided in the discussion, leaving the inquiry open-ended.

anemone
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Is $2017^4+4^{2017}$ a prime?
 
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anemone said:
Is $2017^4+4^{2017}$ a prime?

$$\begin{align*}2017^4+4^{2017}&=(2017^2)^2+(2^{2017})^2 \\
&=(2017^2+2^{2017})^2-2\cdot2017^2\cdot2^{2017} \\
&=(2017^2+2^{2017})^2-2017^2\cdot2^{2018} \\
&=(2017^2+2^{2017}-2017\cdot2^{1009})(2017^2+2^{2017}+2017\cdot2^{1009})\end{align*}$$

$$Q.E.D.$$
 
anemone said:
Is $2017^4+4^{2017}$ a prime?

$2017^4 + 4^{2017}= (2017^2)^2 + (2^{2017})^2 + 2 * 2017^2 * 2^ {2017} - 2017^2 * ( 2^{1009})^2$
= $(2017^2+ 2^{2017})^2 - (2017 * 2^{1009})^2 $
= $(2017^2+ 2^{2017}+ 2017 * 2^{1009}) (2017^2+ 2^{2017}- 2017 * 2^{1009})$

it not a prime

edit: I posted my solution dispite the fact that gregs' solution came but I did not copy it
 
Thanks both for participating! :D
 

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