I seem to remember that there's always a prime between n and 2\*n? (Still an arb... | Hacker News

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		eru on Nov 20, 2013 \| parent \| context \| favorite \| on: Mathematicians Team Up on Twin Primes Conjecture I seem to remember that there's always a prime between n and 2*n? (Still an arbitrarily large absolute gap, but a fixed relative gap.) Can anyone deny or confirm?

DerekL on Nov 20, 2013 | [–]

Yes, that's called Bertrand's postulate, first proven in 1850 by Chebyshev. For any integer n > 3, there's at least one prime strictly between n and 2n-2.

http://en.wikipedia.org/wiki/Bertrand's_postulate

robinhouston on Nov 20, 2013 | [–]

Yes, you are right. http://mathworld.wolfram.com/BertrandsPostulate.html

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