Tagged Questions

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Convergence of $\sum_{n=1}^{\infty}(\frac{H_n}{p_n}-\frac{n}{n^n})$

Does this diverge or converge ?? $$\sum_{n=1}^{\infty}(\frac{H_n}{p_n}-\frac{n}{n^n})$$ where $H_n$ is the nth harmonic number, $p_n$ is the nth prime. My impression is that it diverges, but I don't ...
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How to understand Apostol's proof of the irrationality of $\sqrt{n}$ if $n$ is not a perfect square?

Recently I am reading the textbook of Apostol, Mathematical Analysis, Second Edition. On page 7, there is a theorem 1.10: If $n$ is a positive integer with is not a perfect square, then $\sqrt{n}$ is ...
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$x^2-p=0$, with $p$ prime, have irrational roots.

Unaware that $\sqrt{p}$ is irrational, prove that as $x^2-p=0$ have irrational root for $p$ prime? How would you use the criterion of Eisenstein?
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Proof that the derivative of the prime counting function is the probability of prime?

The derivative of the estimation of the prime counting function, $\frac{x}{ln(x)}$, is $\frac{ln(x)-1}{ln(x)^2}$, which is approximately $\frac{1}{lnx}$ for large values of $x$. According to the prime ...
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$\sum_{i=1}^{k}[\sqrt{ip}]=\frac{p^2-1}{12}$, $p$ is a prime of the form $4k+1$ [duplicate]

$\sum_{i=1}^{k}[\sqrt{ip}]=\frac{p^2-1}{12}$, $p$ is a prime of the form $4k+1$ How to prove this?
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Proving $\lim_{n\to\infty}\left(n-\sum_{k=2}^{n}\frac{1}{\sum_{i=1}^{\infty}\frac{1}{i^k}}\right)=1+\sum_{p\in P}\frac{1}{p\left(p-1\right)}$?

$$\lim_{n\to\infty}\left(n-\sum_{k=2}^{n}\frac{1}{\sum_{i=1}^{\infty}\frac{1}{i^k}}\right)=1+\sum_{p\in P}\frac{1}{p\left(p-1\right)}$$ $P$ is primes. Interesting question ran across while tutoring. ...
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Testing for convergence $\sum_{j=1}^{\infty}\frac{1}{\sum_{i=1}^{j}p_i}$

How would we test for convergence the series below? $$\sum_{j=1}^{\infty}\frac{1}{\sum_{i=1}^{j}p_i}$$ where $p_i$ is the $i$th prime number. I'd be glad to learn an elementary way. Thanks.
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Aside from approximation functions, are there any proven functions that produce an exact $n$th prime?

Aside from approximation functions, are there any functions that produce an exact $n$th prime?
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sum over prime index done by a weird sieve?

As you might have noticed i considered in 2 previous questions sums of the form $f(p_i x)$ where the sum is over the primes $p_i$ ( between some integer bounds : $a \leqslant p_i \leqslant b$ ) , $x$ ...
208 views