Show that $1+\sum_{n=1}^{\infty} \frac{1}{n^2 (n+1)} = \frac{\pi^2}{6}$ without using the Basel Problem.

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From this Approximation method for the Basel Problem, these are equivalent

$$\sum_{n=1}^{\infty} \frac{1}{n^2} = 1+\sum_{n=1}^{\infty} \frac{1}{n^2 (n+1)}$$

Question

There are many Different ways to prove $\sum_{k=1}^\infty \frac{1}{k^2}=\frac{\pi^2}{6}$ (the Basel problem) but are there similar methods to evaluate this series without using the known Basel value $\frac{\pi^2}{6}$ to avoid any circular reasoning?

$$1+\sum_{n=1}^{\infty} \frac{1}{n^2 (n+1)} = \frac{\pi^2}{6}$$

If true, the Basel Series follows by using the transitive property of equality

$$\sum_{n=1}^{\infty} \frac{1}{n^2} = 1+\sum_{n=1}^{\infty} \frac{1}{n^2 (n+1)}$$

and $$1+\sum_{n=1}^{\infty} \frac{1}{n^2 (n+1)} = \frac{\pi^2}{6}$$

then it follows that

$$\sum_{n=1}^{\infty} \frac{1}{n^2} = \frac{\pi^2}{6}$$