Question:medium

Sum of the series to $n$ terms $5 + 7 + 13 + 31 + 85 + \ldots$ is

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When second differences form a GP, $T_n = A \cdot r^{n-1} + B$.

Updated On: Apr 23, 2026

$3^n + 8n + 1$
$\frac{1}{2}\left[3^n + 8n - 1\right]$
$\frac{1}{2}\left(3^n + 8n + 1\right)$
None of the above

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The Correct Option is B

Solution and Explanation

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Sum of the series to \(n\) terms \(5 + 7 + 13 + 31 + 85 + \ldots\) is

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The Correct Option is B

Solution and Explanation

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