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Old 2018-12-30, 14:09   #1
Xyzzy
 
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Default January 2019

http://www.research.ibm.com/haifa/po...nuary2019.html
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Old 2018-12-30, 14:48   #2
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Originally Posted by Xyzzy View Post
I understand why the original numbers work but I don't see too much in the way of extending the problem. edit: okay I see one flaw with the original numbers.

Last fiddled with by science_man_88 on 2018-12-30 at 15:00
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Old 2018-12-30, 17:47   #3
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Here we go again with empty sets and semi empty sets.
Different conventions, conflictingly different solutions.
Makes the challenge flawed in my opinion.

Are primes products of distinct primes?
I would say not, but know of Wikipedia worshippers which would disagree.
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Old 2018-12-30, 17:58   #4
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Originally Posted by a1call View Post
Here we go again with empty sets and semi empty sets.
Different conventions, conflictingly different solutions.
Makes the challenge flawed in my opinion.

Are primes products of distinct primes?
I would say not, but know of Wikipedia worshippers which would disagree.
take the individual sums if you look at them you'll find your answer.
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Old 2018-12-30, 18:14   #5
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Originally Posted by science_man_88 View Post
take the individual sums if you look at them you'll find your answer.
I disagree.

If Primes are products of distinct primes then:

4 > 2 > 1
25 > 5 > 1
100 > 20 > 4 > 2 > 1
121 > 11 > 1

Bob wins.

Else if Primes are-not products of distinct primes then:

4, 25 and 121 have no winners so Alice will have the only choice of choosing 100 and then:

100 > 10 > 1

Bob wins.

Last fiddled with by a1call on 2018-12-30 at 18:16
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Old 2018-12-30, 18:59   #6
science_man_88
 
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Quote:
Originally Posted by a1call View Post
I disagree.

If Primes are products of distinct primes then:

4 > 2 > 1
25 > 5 > 1
100 > 20 > 4 > 2 > 1
121 > 11 > 1

Bob wins.

Else if Primes are-not products of distinct primes then:

4, 25 and 121 have no winners so Alice will have the only choice of choosing 100 and then:

100 > 10 > 1

Bob wins.
false if the sum is a prime square, the only way not to repeat primes is for Alice to take the sqrt and Bob to divide by the sqrt a second time.

Last fiddled with by science_man_88 on 2018-12-30 at 19:00
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Old 2018-12-30, 19:19   #7
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false if the sum is a prime square, the only way not to repeat primes is for Alice to take the sqrt and Bob to divide by the sqrt a second time.
What exactly are you referring to when you say false?
Please be more specific. Thanks.
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Old 2018-12-30, 19:25   #8
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What exactly are you referring to when you say false?
Please be more specific. Thanks.
you're just arguing that because you can assume a bunch of cases don't work that it's ambiguous. it's not. you can complain to the puzzlemaster you know.

Last fiddled with by science_man_88 on 2018-12-30 at 19:25
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Old 2018-12-30, 19:29   #9
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you're just arguing that because you can assume a bunch of cases don't work that it's ambiguous. it's not. you can complain to the puzzlemaster you know.
I am saying that two different conventions will both work and that's why the challenge is vague.
And frankly I don't need you to let me know if I can or can not raise the issue with anyone.
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Old 2018-12-30, 19:38   #10
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Originally Posted by a1call View Post
I am saying that two different conventions will both work and that's why the challenge is vague.
And frankly I don't need you to let me know if I can or can not raise the issue with anyone.
many different conventions work in code as well, you don't complain about that. my point is if you want it to be unvague you can get an explanation from the puzzlemaster not here.
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Old 2018-12-30, 23:41   #11
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Quote:
Originally Posted by a1call View Post
Here we go again with empty sets and semi empty sets.
Different conventions, conflictingly different solutions.
Makes the challenge flawed in my opinion.

Are primes products of distinct primes?
I would say not, but know of Wikipedia worshippers which would disagree.
1 is NOT a prime by definition. The smallest prime is 2.

So primes are NOT a product of distinct primes, because a product is defined by at least 2 terms.
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