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7 votes
1 answer
209 views

What is the product of the areas of every regular polygon inscribed in a circle of area $1$?

What is a closed form of $P=\prod\limits_{k=3}^{\infty}\frac{k}{2\pi}\sin{\left(\frac{2\pi}{k}\right)}\approx 0.05934871...$ ? This is the product of the areas of every regular polygon inscribed in a ...
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2 votes
4 answers
270 views

Show that $\lim_{n\to\infty}n\left(n\ln{n}+\ln{\sqrt{2}}-n-\sum_{k=1}^n \ln{\left(k-\frac{1}{2}\right)}\right)=\frac{1}{24}$.

I am trying to show that $$L=\lim\limits_{n\to\infty}n\left(n\ln{n}+\ln{\sqrt{2}}-n-\sum\limits_{k=1}^n \ln{\left(k-\frac{1}{2}\right)}\right)=\frac{1}{24}$$ Desmos strongly suggests that this is true,...
Dan's user avatar
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5 votes
0 answers
131 views

Infinite product of areas in a square, inscribed quarter-circle and line segments.

The diagram shows a square of area $An$ and an enclosed quarter-circle. Line segments are drawn from the bottom-left vertex to points that are equally spaced along the quarter-circle. The regions ...
Dan's user avatar
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6 votes
2 answers
270 views

What is a closed form of this limit? (product of areas in circle with parabolas)

I am looking for a closed form of $L=\lim\limits_{n\to\infty}\prod\limits_{k=1}^n \left(\left(6+\frac{4n}{\pi}\left(\sin{\frac{\pi}{2n}}\right)\left(\cos{\frac{(2k-1)\pi}{2n}}\right)\right)^2-\left(\...
Dan's user avatar
  • 25.7k