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For n ≥ 2, let S_n denote the set of all subsets of 1,2 … . . ., n with no two consecutive numbers. For example 1,3,5 ∈ S_6, but 1,2,4 ∉ S_6. Then n…

JEE Main 2025 — Mathematics Algebra

2025integereasy

For n≥2\mathrm{n} \geq 2n≥2, let SnS_nSn​ denote the set of all subsets of {1,2…...,n}\{1,2 \ldots . . ., n\}{1,2…...,n} with no two consecutive numbers. For example {1,3,5}∈S6\{1,3,5\} \in \mathrm{S}_6{1,3,5}∈S6​, but {1,2,4}∉S6\{1,2,4\} \notin \mathrm{S}_6{1,2,4}∈/S6​. Then n( S5)n\left(\mathrm{~S}_5\right)n( S5​) is equal to ________

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Held on 7 Apr 2025 · Verified 6 Jul 2026.

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