Re: Prime Puzzle with Mathematica [CORRECTION]
- To: mathgroup at smc.vnet.net
- Subject: [mg92712] Re: [mg92680] Prime Puzzle with Mathematica [CORRECTION]
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Sat, 11 Oct 2008 06:43:59 -0400 (EDT)
- Reply-to: hanlonr at cox.net
This can be written more compactly as
Select[Subsets[p, {3}], And @@ PrimeQ /@ Mean /@ Subsets[#, {2, 3}] &]
Bob Hanlon
---- Bob Hanlon <hanlonr at cox.net> wrote:
=============
p = Table[Prime[i], {i, 5, 25}]
{11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97}
Select[Subsets[p, {3}],
And @@ (PrimeQ /@ (Mean /@ Drop[Subsets[#], 4])) &]
{{11, 47, 71}}
Bob Hanlon
---- amzoti <amzoti at gmail.com> wrote:
=============
Hi All,
trying to find an efficient way to this in Mathematica.
I found the answer - but it was a manual list manipulation - and it
was ugly!
Any suggestions?
3 Nice Primes:
Find three 2-digit prime numbers such that:
* The average of any two of the three is a prime number, and
* The average of all three is also a prime number
Thanks!
~A
--
Bob Hanlon
--
Bob Hanlon