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You are not logged in. #1 20130615 18:38:51
Prime numbersFind all sets of 4 different prime numbers (a, b, c, d) with such that the sum of any three out of these four primes are also prime.In other words, find positive integers a, b, c, d such that a, b, c, d, a+b+c, a+b+d, a+c+d and b+c+d are eight different primes. #2 20130615 19:55:30
Re: Prime numbersHi phanthanhtom; because of this
And I am finding many solutions. Perhaps there are an infinite number. Or perhaps something is wrong in my method. In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #3 20130615 21:23:22
Re: Prime numbersThere might be an infinite number of solutions. I think so. #4 20130616 14:11:10
Re: Prime numbersOne more problem: #5 20130617 21:14:04
Re: Prime numbers{{a, b, c, d}} In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. 