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$$\lim_{n \to \infty} \left(1 + \frac{1 + \frac{1}{2} + \ldots + \frac{1}{n}}{n^2}\right)^n$$ is equal to
Given,
$$\lim_{n\to\infty}\left(1+\frac{1+\frac12+\cdots+\frac1n}{n^2}\right)^n$$
Let
$$H_n=1+\frac12+\cdots+\frac1n$$
Then expression becomes
$$\lim_{n\to\infty}\left(1+\frac{H_n}{n^2}\right)^n$$
Now,
$$H_n\sim\log n$$
Hence,
$$\frac{H_n}{n^2}\to0$$
Using standard result,
$$\left(1+\frac{a_n}{n}\right)^n\to e^L \quad \text{if } a_n\to L$$
Here,
$$a_n=\frac{H_n}{n}\to0$$
Therefore,
$$\left(1+\frac{H_n}{n^2}\right)^n\to e^0$$
$$=1$$
Hence, the required limit is
$$\boxed{1}$$
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