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I was asked this by a friend. Hoping someone to answer. The goal here is to find a general formula for the expression.

bjcolby15
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frog
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1 Answers1

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For these problems, you can always search the OEIS with the first few terms.

https://oeis.org/search?q=1%2C28%2C3153&sort=&language=english&go=Search

You see that this sequence has been considered by others before, that there's no known exact formula (at least not there, but I have a feeling there's likely no closed formula at all), but there is an asymptotic estimate.

justt
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