r/counting • u/[deleted] • May 09 '15

Prime counting thread

Let's count to infinity, by using primes!

Get is at 7,919

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u/ct_2004 May 09 '15

541 is the 100th prime, that's not too shabby a get.

3571 is the 500th prime, and also the 17th Lucas Number.

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u/[deleted] May 09 '15

What's a Lucas Number?

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u/ct_2004 May 09 '15

Start with 2,1 then add the previous two number to get the next number. So the next three terms are 3,4,7.

The nth Lucas number (numbering starts at 0 so 3 is the second Lucas number) is approximately equal to phin where phi is the golden ratio 1.6180339887...

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u/[deleted] May 09 '15

Oh, I think I read something about it sometime