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Results tagged with closed-form-expressions
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user 5534
For questions that specifically ask for determining a closed form of equations, integrals etc.
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Sum of subset of geometric series: a^2^n
The formula for 1 + a + a^2 + .... where 0 < a < 1 is $\frac{1}{1-a}$, but what if you wanted to sum only those where the exponent is a power of 2? That is,
$S = a + a^2 + a^4 + a^8 + \cdots$
I fee …
- 2,019