MHB What Natural Numbers Solve the Equation from POTW #421?

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The equation presented involves finding natural numbers \( x \) that satisfy the identity \( \dfrac{1^4}{x}+\dfrac{2^4}{x+1}+\dfrac{3^4}{x+2}+\cdots+\dfrac{10^4}{x+9}=3025 \). Members castor28 and kaliprasad successfully provided correct solutions. The discussion highlights the process of solving the equation and verifying the results. The focus remains on the mathematical approach and the validation of the solutions. This problem emphasizes the exploration of natural numbers in algebraic identities.
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Here is this week's POTW:

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Solve for natural numbers for the identity below:

$\dfrac{1^4}{x}+\dfrac{2^4}{x+1}+\dfrac{3^4}{x+2}+\cdots+\dfrac{10^4}{x+9}=3025$

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Congratulations to the following members for their correct solution! (Cool)

1. castor28
2. kaliprasad

Solution from castor28:
We use the fact that $\displaystyle\sum_{k=1}^n{k^3}=\frac{n^2(n+1)^2}{4}$.

For $x=1$, the LHS becomes:
$$
1^3 + 2^3 + \cdots + 10^3 = \frac{10^2\cdot 11^2}{4}=3025
$$

As this is the required value, $x=1$ is a solution. As the LHS is a decreasing function of $x$, this is the only solution.
 

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