## #math - Sat 10 Mar 2007 between 00:07 and 00:57

### NY Lost Funds

 MizardX Recursivly you could on each level check in which triangle the point goes. If it's in the middle one, you know that it's not in the fractal. Otherwise continue recursion. StyxAlso Say that I know that there's a chance p that it will rain today. If it rains today, there's a chance alpha that it rains tomorrow (conditional prob.). If it doesn't rain today, there's a chance beta that it doesn't rain tomorrow.What is the chance that it rains tomorrow? Olathe You could determine if it's on a triangle boundary line or not.You can take the x position in binary to determine which removed triangles to check. Rotate the triangle 120 degrees and repeat. And so on. If the triangles to check in each set will intersect to give one or zero triangles.That might only work for rational points, though. prettytoney Hi. logic_grrl i am having trouble trying to understand how to break down some propositions for automated theorem proving tabber Hi, if I have Sum(n=2..oo) x^(n) and im asked to compute thederivate, would that be Sum(n=2..oo) n*x^(n-1) ? Olathe tabber: Yes, if the original sum and final sum is finite. chessguy logic_grrl: can you be a little more specific? tabber Olathe: thanks Olathe tabber: No problem. logic_grrl chessguy, www.people.fas.harvard.edu/~albert/cscie220/Asst6.pdf chessguy logic_grrl: what about it? logic_grrl chessguy, i just dont see how to go about it Olathe logic_grrl: What is an example proposition and its breakdown ? logic_grrl Olathe, well the easiest one is P and ~P chessguy Olathe: they give example input logic_grrl which cant be true Olathe I hate PDFs. logic_grrl but how do you show this using this methodOlathe, http://209.85.165.104/search?q=cache:QFxw7TAsTQ0J:www.people.fas.harvard.edu/~albert/cscie220/Asst6.pdf+propositional+resolution+theorem+prover&hl=en&ct=clnk&cd=1&gl=us&client=firefox-a^ htl version chessguy it looks to me like the problem is explained pretty thoroughly tabber can anyone help me with exponental generating functions?anyone? Olathe tabber: You have to tell us what problem you're having or we won't know if we can help you. tabber ok, im asked to prove that psi''(x) = psi'(x) + psi(x), psi being the exponential generating function of the fibonacci sequence a_n = a_(n-1) + a_(n-2) for n>=2 and a_0 = a_1 = 1would the egf be (Sum(n=2..oo) (a_(n-1)+a_(n-2))/n! * x^n) + x + 1 ? Is that correct? Olathe I think it is. tabber hmm im stuck at the sum .... Olathe What do you mean ? psi'(x) + psi(x) ? tabber yeah Olathe You have psi'(x) ? tabber i have Sum(n=2..oo) (a_(n-1)+a_(n-2))/n! * x^n + x + 1 + Sum(n=2..oo) (a_(n-1)+a_(n-2))/n! *nx^(n-1) Olathe Alright. Add like terms.Like if you have x^3 + x^2 + x + 1 + 3x^3 + 2x^2 + x + 1, you can add it together. Same thing here. yi off topic, any one familiar with tex and including graphics in it?http://pastie.textmate.org/45987