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You are not logged in. #1 20060228 15:50:12
Probability and StatisticsPS # 1 Character is who you are when no one is looking. #2 20060301 03:15:56
Re: Probability and StatisticsPS # 1 Why did the vector cross the road? It wanted to be normal. #3 20060301 03:41:45
Re: Probability and StatisticsVery good, mathsyperson. You're correct. Character is who you are when no one is looking. #4 20060301 19:08:07
Re: Probability and StatisticsPS # 2 Character is who you are when no one is looking. #5 20060302 02:47:18
Re: Probability and StatisticsOoh, interesting. Let's see... a chessboard has 4 corner squares, 24 edge squares and 36 centre squares. Why did the vector cross the road? It wanted to be normal. #6 20060302 02:58:37
Re: Probability and StatisticsExcellent! Well done, mathsyperson! Character is who you are when no one is looking. #7 20060302 15:19:11
Re: Probability and StatisticsPS # 3 Character is who you are when no one is looking. #8 20060303 03:31:26
Re: Probability and StatisticsP(AnB) = P(A) + P(B)  P(AuB). Why did the vector cross the road? It wanted to be normal. #9 20060303 15:43:36
Re: Probability and Statistics
mathsyperson, did you notice that? Character is who you are when no one is looking. #10 20060309 15:17:05
Re: Probability and StatisticsPS # 4 Character is who you are when no one is looking. #11 20060310 04:01:25
Re: Probability and StatisticsOh, silly me. I hate it when I make stupid mistakes from not reading the question properly. Ah well. Why did the vector cross the road? It wanted to be normal. #12 20060310 15:13:39
Re: Probability and StatisticsExcellent, mathsyperson! Character is who you are when no one is looking. #13 20091012 08:35:44
Re: Probability and StatisticsHi, could you please answer this problem? #14 20091012 09:46:43
Re: Probability and StatisticsHi maudish; Last edited by bobbym (20091012 09:50:38) 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. #15 20091013 13:59:42
Re: Probability and StatisticsHi maudish; The series can be eliminated because we only seek the coefficient of x^2 ( 2 rooks). Also since the board is square r = c. So. The above is the number of 2 non attacking rooks on a c x c chessboard. From a combinatorical argument and playing much spot the pattern. We can solve for n and clean up: Where n is the number of ways 2 rooks can be positioned on the white squares of a c x c chessboard when c is even. The above will generate the table given in the previous post, i.e. c = 2 then n = 0 c = 4 then n = 8 c = 6 then n = 36 c = 8 then n = 96 c = 10 then n = 200 . . . This is not a proof, just a conjecture. I have tested it for c = 16 by direct count. I suppose it might be proven by induction but the correct method is by partitioning the chessboard with it's forbidden black squares into disjoint boards and then using the rook polynomials to prove it. When I do that I will post it. Last edited by bobbym (20091013 14:17:55) 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. #16 20110301 16:42:16
Re: Probability and StatisticsIf I'm not wrong. Last edited by Gman (20110301 17:22:56) Maths!...... #17 20110301 17:00:15
Re: Probability and StatisticsHi Gman; 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. 