Class JEE Mathematics Sets, Relations, and Functions Q #1121
COMPETENCY BASED
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4 Marks 2025 JEE Main 2025 (Online) 7th April Morning Shift NUMERICAL
For $n \geq 2$, let $S_n$ denote the set of all subsets of $\{1,2, \ldots, n\}$ with no two consecutive numbers. For example $\{1,3,5\} \in S_6$, but $\{1,2,4\} \notin S_6$. Then $n\left(S_5\right)$ is equal to ________

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