# Tag Info

Accepted

### How to calculate $\prod\limits_{p}\frac{p^2+1}{p^2-1}$?

A Trace reveals the problem: ...

### François Viète's approximation to π

You could use VietePiApprox[n_] := (Times @@ NestList[Sqrt[2 + #] &, Sqrt, n])/ 2^(n + 1) SetAttributes[VietePiApprox, Listable] which approximates Pi as ...

### Infinite product for Zeta?

Amplifying on answer by @rhermans ...
Accepted

### Infinite product for Zeta?

Product[ (1296 n^4 (1 + (1 + n)^3))/((-1 + 36 n^2)^2 (-1 + (1 + n)^3)) , {n, 1, ∞} ] === Zeta True ...
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### How to compute the partial trace of a 4x4 matrix?

Your example can be achieved using Map with a level specification, Partition to generate the sub-matrices and ...

### François Viète's approximation to π

Well, FoldList also can finish this job: 2/Times @@ (1/2 FoldList[Sqrt[2 + #] &, ConstantArray[Sqrt[2.], 10]]) By the way,...
Accepted

### Closed form of product of Gamma function

Workaround: $$\Gamma \left(\frac{k}{n}\right)=\frac{\Gamma \left(\frac{k}{n}+1\right)}{\frac{k}{n}}$$ ...