Tìm $n \in N$, biết rằng:
1) $C^2_{n+1}+2C^2_{n+2}+2C^2_{n+3}+C^2_{n+4}=149$
2) $C^0_{2n}+3^2C^2_{2n}+3^4C^4_{2n}+...+3^{2n}C^{2n}_{2n}=2080$
3) $\frac{A^0_n}{0!}+\frac{A^1_n}{1!}+...+\frac{A^n_n}{n!}=4096$
4) $nC^0_n+(n-1)C^1_n+(n-2)C^2_n+...+C^{n-1}_n=1024$
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