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A continued fraction for $\frac{3\sqrt{3}}{\pi}$

I found the following continued fraction identity:$$\frac{3\sqrt3}{\pi}=1+\cfrac{1}{1+\cfrac{2}{2+\cfrac{3}{1+\cfrac{4}{3+\cfrac{5}{1+\cfrac{6}{\ddots}}}}}}.$$The partial numerators...

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Is there an integral that proves $\pi > 333/106$?

The following integral,$$ \int_0^1 \frac{x^4(1-x)^4}{x^2 + 1} \mathrm{d}x = \frac{22}{7} - \pi $$is clearly positive, which proves that $\pi < 22/7$.Is there a similar integral which proves $\pi...

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Repeating digits in pi

Running an experiment to see how many times different integers of different lengths repeat themselves in the first million digits of pi(searched number: how many times it appears)When searching 1...

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Is there a known geometric framework viewing mixed-radix numeration,...

I'm looking for references (or a name) for a picture that seems to unify several classical objects. I'd like to know whether it already exists in the literature, and if so under what name.The picture....

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Why is the expected value of this random nested radical equal to $4/\pi$?

To celebrate Pi Day, I took a look at some classic identities for $\pi$ again, particularly the nested roots associated with Viète’s formula. Such as this one:$$\pi=\lim_{k \to\infty} 2^k...

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A continued fraction for Baxter's four-coloring constant

I found the following infinite continued fraction:$$\operatorname{C_{B4CC}}=\cfrac{2}{1+\cfrac{2}{1+\cfrac{6}{1+\cfrac{3}{1+\cfrac{10}{1+\cfrac{4}{\ddots}}}}}}$$where $\operatorname{C_{B4CC}}$ denotes...

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Distribution of the digits of $\pi$

Can anything be stated about the distribution of the digits of $\pi$, i.e., if I were to sample $n$ digits of $\pi$, can anything be said about the probability to observe certain digits, or is there...

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A continued fraction for the reciprocal of Gauss's constant

I found the following infinite continued fraction:$$\frac{1}{G} = \frac1{(2\pi)^{-3/2}\,\Gamma^2(1/4)} = \cfrac{4}{1+\cfrac{5}{1+\cfrac{6}{1+\cfrac{9}{1+\cfrac{8}{1+\cfrac{13}{\ddots}}}}}}$$where $G$...

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Is it mathematically correct to write $e^{i\pi}=i^2$?

I know that Euler's identity gives $e^{i\pi}=-1$, and since $i^2=-1$, it follows that $e^{i\pi}=i^2$.My questions are:Is it mathematically correct to write $e^{i\pi}=i^2$, or is this considered poor...

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Proving $\pi^3 \gt 31$

$$\large \pi^3 \gt 31$$Using a calculator, $\pi^3/31 \approx 1.0002$, so I thought this may be challenging to do by hand.It is extremely easy with the use of any calculator, so I was wondering now:Can...

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About Legendre's like relations generalizations.

ContextBeing:$$K(k)=\int_{0}^{\pi/2}\frac{dt}{\sqrt{1-k^2\sin^2{t}}}=\frac{\pi}{2}\sum_{n=0}^{\infty}\frac{(2n)!^2k^{2n}}{2^{4n}n!^4},\hspace{.5cm}k...

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Does every digit in base $n$ appear in the expansion of $\pi$? [duplicate]

So I was thinking of the conjecture that every finite combination of digits appears somewhere in the expansion of $\pi$. This led me to a wonder:For every integer base $n \ge 2$, does every digit...

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What is the probability of a specific sequence of 11 digits occurring in a...

This isn't homework. I'm actually wondering how likely it is that any particular 11-digit telephone number will occur in the first billion digits of $\pi$. My probability course was way too long ago,...

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On Ramanujan's fastest series.

ContextWith some effort we can show that Ramanujan's fastest series implies:\begin{align}\frac{8E(k_{58})K(k_{58})}{\pi^2}-\frac{aK^2(k_{58})}{\pi^2}=\frac{\sqrt{58}}{29\pi},\tag{1}\end{align}with:...

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eliminate the trigonometric transcendence of $\pi$ [closed]

Is...

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Proof of an Elliptic Integral Relation

In celebration of Pi Day, I messed around with the following Ramanujan formula:$$\sum_{n=0}^{\infty} \binom{2 n}{n}^3 \frac{42 n+5}{2^{12 n+4}} = \frac1{\pi} $$It turns out that, through some...

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Approximation of $\pi$ by approximating different distributions

I think I found an approximation for $\pi$. I know, there are like $10,000$ approx., but I gave it a try. I found the following expression:$$\pi \approx...

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How does this telescoping infinite product linking $e$ and $\pi$ work? [closed]

I recently encountered a paper titled "A Masterclass in Pure Rational Geometry & Analytical Limits" (dated June 7, 2025). Section 4 of the document presents a striking identity that expresses $\pi$...

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Is this two-stage continued-fraction approximation just a disguised...

I would like to understand how to classify the following approximation to $\pi$.Define$$N(a)=\sqrt{\frac{\pi}{\sqrt{\frac{\pi}{\sqrt{\pi}a}}}}.$$A direct simplification...

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How can this two-stage continued-fraction approximation to pi be classified?...

I am looking for references or known related constructions for the following elementary approximation to $\pi$. It arises from the repeating...

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