Problem 1103 (difficulty: 4/10)

\(\displaystyle \frac1{1\cdot2\cdot3}+ \frac1{2\cdot3\cdot4}+ \frac1{3\cdot4\cdot5}+ \frac1{4\cdot5\cdot6}+ \ldots=? \)

Give me another random problem!

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Request for a concrete problem:I want problem no.

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