Talk:Sexy prime

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I changed "such that p + 18 is composite " to "prime" . Please someone change back if it is wrong, but the examples are prime and it makes more sense as prime.

Walt 20:37, 4 April 2006 (UTC)

Ooops! - put it back, I had missed that it was the first one _not_ in the triplet that is not prime.

Walt

[edit] Sexy twin primes?

Is there a name for sexy pairs of twin primes, i.e. sets of four primes of the form (x, x+2, x+6, x+8)? The first four such sets are (5, 7, 11, 13), (11, 13, 17, 19), (101, 103, 107, 109), (191, 193, 197, 199). It is easily proven that for all "sexy twin primes" except (5, 7, 11, 13), x mod 210 must be 11, 101, or 191. --12.34.246.38 21:18, 4 August 2006 (UTC)

It's called a Prime quadruplet. --PrimeHunter 22:52, 4 August 2006 (UTC)

Ah! Okay, thanks! --12.34.246.38 18:14, 8 August 2006 (UTC)

Um, Actually, no it's not. That would be (x, x+2, x+4, x+6). This is quite different. There's no word for this, really, as it's pretty much an arbitrary pattern. A lot of cool patterns just don't have names, just because there's so many of them that it doesn't make sense to try naming them all. -- Aljo September 13, 2006

Did you look at the Prime quadruplet article? It is easily proven that there are no sets of primes of the form {x, x+2, x+4, x+6} (with the dubious exception of {1, 3, 5, 7} if you consider 1 a prime, which most mathemeticians do not). In fact, in any group of three numbers of the form {x, x+2, x+4}, one will always be a multiple of 3, so the only way they could all be prime is if 3 itself is one of them, as is the case for {3, 5, 7}. --Mwalimu59 16:27, 13 September 2006 (UTC)