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A problem of infinite series

Algebra Level 3

\[ \large \dfrac{1}{3^2+1}+\dfrac{1}{4^2+2}+\dfrac{1}{5^2+3}+ \cdots + \dfrac1{(n+2)^2 + n} + \cdots = \, ? \]

\[\frac{13}{36}\] \[\frac{10}{20}\] \[\frac{12}{24}\] \[\frac{8}{16}\]

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by James Christian

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