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A calculus problem by neelesh vij

Calculus Level 5

\[ \large A = \displaystyle \sum_{m=1}^{\infty} \sum_{n=1}^{\infty} \dfrac{m^2n}{4^m (n4^m+m4^n)} \]

Find \(81A\).

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Excel in math and science

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by neelesh vij

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