## How much is

The product ranges over all primes. In other words,

Just heard it from Avinoam Mann.

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%d bloggers like this:

Well, it is 2,5. But how do you prove that? Would be awesome to see an argument for that 😀

See e.g., this: https://mathoverflow.net/q/164092/37266

I thought to write 2. But then I read I am allowed to think, so I noticed this look like zeta product and got zeta(2)^2/zeta(4) which if i am not wrong gives 8/3

It’s actually 5/2, but yeah 🙂

What a surprise! I’m not a programmer, but I was quickly able to get Mathematica to tell my the product up to the 10,000th prime, and it’s pretty clear what the answer will be in the limit. Now to figure out why…

Euler worked it out.

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Gil, could you please email me? Thanks, Jan Grabowski (Lancaster)

Yes, sure, sorry for the delay, Jan. See you soon, best –Gil

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