Analysis: The left algebraic expression is similar to the expansion of the binomial theorem, which can be associated with the binomial theorem, and the problem can be solved easily. Proof: ∵Cn1+Cn2+⋯+Cnn ∴Cn1+=2n−1=2−12n−1=1+2+22+23+⋯+2n−1>nn21+2+⋯+(n−1)=n⋅22n−1,Cn2+⋯+Cnn>n⋅22n−1(n⩾2).
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