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Viewing Version 1 of 'Germain prime'
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Title of object: Germain prime
Canonical Name: GermainPrime
Type: Definition

Created on: 2004-09-03 04:46:59
Modified on: 2004-09-03 04:46:59

Creator: vmoraru
Modifier: vmoraru
Author: vmoraru

Classification: msc:11-XX

Revision comment (for changes between this and next version):

Changes for correction #6010 ('reclassify').

Preamble:

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Content:

A prime number $p$ is called a \emph{Germain prime} or \emph{Sophie Germain prime} if $2p+1$ is also prime.

The first few Sophie Germain primes are:
$2, 3, 5, 11, 23, 29, 41, 53, 83, 89, 113, 131, 173, 179, 191, 233,...$

A estimate for the number of Germain primes less than $n$ is $\frac{2cn}{\ln^2{n}}$, where $c$ is the twin prime constant.
It is conjectured that there are infinitely many Germain primes, but like the twin prime conjecture, this has not been proven.