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An algebra problem by Pi Han Goh

Algebra Level 4

If \( A = \displaystyle \sum_{n=1}^\infty \frac {1}{n(n+1)(n+2)(n+3)(n+4)(n+5)} , \) what is the value of \(\frac {1}{A}?\)

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Excel in math and science

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by Pi Han Goh

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