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Jan 6, 2015 at 19:40 answer added The Masked Avenger timeline score: 0
Jan 6, 2015 at 19:23 comment added The Masked Avenger This will also follow from the assertion that for n large enough, all but 6 positive integers between 0 and S_n, the sum of the first n primes, are realized as a subset sum, with the exceptions smaller than 7 or bigger than S_n - 7.
S Jan 6, 2015 at 18:58 history suggested alexwlchan CC BY-SA 3.0
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S Jan 6, 2015 at 18:58
Aug 15, 2010 at 11:52 vote accept user8140
Aug 15, 2010 at 11:30 vote accept user8140
Aug 15, 2010 at 11:50
Aug 13, 2010 at 9:22 answer added dvitek timeline score: 5
Aug 10, 2010 at 17:18 comment added S. Carnahan Sorry, by "small case analysis at the end" I meant that the smallest primes needed to be arranged by hand, not that the greedy algorithm could be proved to work by case analysis.
Aug 5, 2010 at 6:57 comment added user8140 Thank you, Scoot,Mariano. @Mariano,Yes! According to the greedy algorithm: (31+19+17+7+5) -(29+23+13+11+3)=79-79=0, then how to put 2? While (31+29+17+3)=80, 23+13+19+11+7+5+2=80, to be more beautiful, 31+29-23-19+17-13-11-7-5+3-2=0
Aug 5, 2010 at 5:57 vote accept user8140
Aug 5, 2010 at 6:58
Aug 5, 2010 at 5:48 comment added Mariano Suárez-Álvarez @Scott, I think that when you start with the first 11 primes that greedy algorithm does not work.
Aug 5, 2010 at 5:11 comment added Mariano Suárez-Álvarez Google should find various algorithms to solve the so-called partition problem en.wikipedia.org/wiki/Partition_problem, which can be solved efficiently in lots of cases, it seems.
Aug 5, 2010 at 5:11 comment added S. Carnahan There is no need to write a program, because the statement is true. Fix n, and starting from the largest prime in P[n] and following decreasing order, put each prime into the pile with the smaller sum. Standard estimates like Bertrand's postulate (and improvements - see Wikipedia) imply the difference between the two piles will be less than, say, 3/2 the next prime on the list. This reduces to a small case analysis at the end.
Aug 5, 2010 at 5:02 answer added Darsh Ranjan timeline score: 1
Aug 5, 2010 at 4:15 history edited user8140 CC BY-SA 2.5
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Aug 5, 2010 at 4:04 history asked user8140 CC BY-SA 2.5