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veganclimber
Jul 9, 2010, 3:48 AM
Post #26 of 32
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hafilax wrote: Speaking of factorials, I learned a new notation from my students this year while working with Bessel functions: n!!=n!(n+1)!. Didn't know that one before and almost marked them wrong thinking it meant (n!)!. I knew that the student is smarter than me so I looked it up. He did better than the prof who kept giving me wrong answers in the solution guides.
That's interesting. I have seen a different definition:
http://mathworld.wolfram.com/DoubleFactorial.html
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hafilax
Jul 9, 2010, 5:37 AM
Post #27 of 32
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veganclimber wrote: hafilax wrote: Speaking of factorials, I learned a new notation from my students this year while working with Bessel functions: n!!=n!(n+1)!. Didn't know that one before and almost marked them wrong thinking it meant (n!)!. I knew that the student is smarter than me so I looked it up. He did better than the prof who kept giving me wrong answers in the solution guides. That's interesting. I have seen a different definition: http://mathworld.wolfram.com/DoubleFactorial.html
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skiclimb
Jul 9, 2010, 7:04 AM
Post #28 of 32
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truello wrote: skiclimb wrote: petsfed wrote: By comparison, factorial grows at a snail's pace. And I am aware of the definition of flops, Tristan. There's just a difference between FLOPs (FLoating-point OPerations) and FLOPS (FLoating-point Operations Per Second) which creates some ambiguity. Perhaps... hell it's been years since i really had to use statistics.. Look at it this way... S_3 = 19683 3! = 6
Gotcha now..just had never seen that notation..and was really drunk when reading this post first time..
i'm only slightly drunk atm.. the notation is nifty but is there a real world application? what situation would such notation be representative of
hell it would graph for all intents and purposes as a vertical line with a very short pause in front. hmm kinda cool though that it still would have an x value to infinity .. so its a vertical line with infinite width..lol
Question since we have these related types of notation is there a notation for
the concept being 3^0+3^1+3^2+3^3 other integers folowing same pattern?
(This post was edited by skiclimb on Jul 9, 2010, 7:18 AM)
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petsfed
Jul 9, 2010, 5:42 PM
Post #29 of 32
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skiclimb wrote: truello wrote: skiclimb wrote: petsfed wrote: By comparison, factorial grows at a snail's pace. And I am aware of the definition of flops, Tristan. There's just a difference between FLOPs (FLoating-point OPerations) and FLOPS (FLoating-point Operations Per Second) which creates some ambiguity. Perhaps... hell it's been years since i really had to use statistics.. Look at it this way... S_3 = 19683 3! = 6 Gotcha now..just had never seen that notation..and was really drunk when reading this post first time.. i'm only slightly drunk atm.. the notation is nifty but is there a real world application? what situation would such notation be representative of hell it would graph for all intents and purposes as a vertical line with a very short pause in front. hmm kinda cool though that it still would have an x value to infinity .. so its a vertical line with infinite width..lol Question since we have these related types of notation is there a notation for the concept being 3^0+3^1+3^2+3^3 other integers folowing same pattern?
Since that one is just summing, its pretty easy.
Your core expression is x^n, and you just have a sum of all the possible integer n's from zero to infinity. Unfortunately, I'm having real difficulty finding a way to express that on a computer screen without using an exterior program.
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jt512
Jul 9, 2010, 6:30 PM
Post #30 of 32
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petsfed wrote: skiclimb wrote: truello wrote: skiclimb wrote: petsfed wrote: By comparison, factorial grows at a snail's pace. And I am aware of the definition of flops, Tristan. There's just a difference between FLOPs (FLoating-point OPerations) and FLOPS (FLoating-point Operations Per Second) which creates some ambiguity. Perhaps... hell it's been years since i really had to use statistics.. Look at it this way... S_3 = 19683 3! = 6 Gotcha now..just had never seen that notation..and was really drunk when reading this post first time.. i'm only slightly drunk atm.. the notation is nifty but is there a real world application? what situation would such notation be representative of hell it would graph for all intents and purposes as a vertical line with a very short pause in front. hmm kinda cool though that it still would have an x value to infinity .. so its a vertical line with infinite width..lol Question since we have these related types of notation is there a notation for the concept being 3^0+3^1+3^2+3^3 other integers folowing same pattern? Since that one is just summing, its pretty easy. Your core expression is x^n, and you just have a sum of all the possible integer n's from zero to infinity. Unfortunately, I'm having real difficulty finding a way to express that on a computer screen without using an exterior program.
I think what he's looking for is this:
tex2png -T -c '$\f orall n \in \{1,2,3,\ldots\}\; S_n = \sum_{m=0}^{n}n^m$'
Jay
(This post was edited by jt512 on Jul 9, 2010, 7:34 PM)
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hafilax
Jul 9, 2010, 7:36 PM
Post #31 of 32
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I think the sum goes to n instead of infinity.
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jt512
Jul 9, 2010, 7:39 PM
Post #32 of 32
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hafilax wrote: I think the sum goes to n instead of infinity.
Yeah, I just realized that that was what he meant, and I changed it while you were posting.
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