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Can anybody see a mathematical relationship here?

  1. May 23, 2005 #1
    Hi. I was playing with the square of numbers for a few hours, and I can up with this set of numbers, can anybody show me a relationship?

    P X D
    ______
    2 2 2
    _______
    3 3 6
    _______
    4 4 24
    _______
    5 5 120
    _______

    I cannot see a relationship :surprised But there has to be. Any help?


    --eNathan (3.14)
     
  2. jcsd
  3. May 23, 2005 #2

    Curious3141

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    What exactly were you playing around with ? That'll help us to explain the relationship better.

    Anyway, [tex]2 ! = 2, 3 ! = 6, 4 ! = 24, 5 ! = 120[/tex], the last column appears to comprise factorials of the identical first two column numbers.
     
  4. May 23, 2005 #3
    What do all the '!' mean? I though != is innequality <>
     
  5. May 23, 2005 #4

    Curious3141

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    No that's computer speak (for example, C programming uses that).

    '!' in Maths is factorial. [tex]n! = 1.2.3....(n-1)(n)[/tex], the sequential product of all natural numbers less than or equal to n. It is only defined for nonnegative integers, with 0! = 1 (by definition). (There is an extension of factorial for non-integers called the gamma function, but you don't have to worry about that for now).

    OK, so what were you doing, maybe I or someone else can help you understand the pattern.
     
    Last edited: May 24, 2005
  6. May 24, 2005 #5

    uart

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    n, n, n! Other than that what were you looking for?
     
  7. May 24, 2005 #6
    I am asking, givin this set

    P X D
    ______
    2 2 2
    _______
    3 3 6
    _______
    4 4 24
    _______
    5 5 120

    I am saying, is there any way to mathematicly manipulate P, and X to get the value of D? For the first one, I guess you could do P / X * P = D, but that would not work for the second one. For the second one you could do P + X = D, but that would not work for the third one. And I dont even know how you can mathematicly manipulate 4 and 4 to get 24, I suppose (PX + (2X)) but that makes no sense. I will try to explain how I got these numbers when I have the time I am at school ATM.
     
  8. May 24, 2005 #7

    matt grime

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    The answer, from that set, is D=P! and is independent of X (though as X=P that is debatable).

    I think everyone wishses you to state what P, X and D are.
     
  9. May 24, 2005 #8

    uart

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    Yes of course. As already pointed out D=factorial(P) and X is just redundant.
     
  10. May 24, 2005 #9
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