Math

Project Euler problem 140
Hello everyone, I am trying to solve this problem but i am not getting efficient solution. Here is my analysis. A=(x^2+3x)/(1-x-x^2) x=-(A+1)+Sqrt(5A^2+14A+1)/2(A+3) since x is rational so 5A^2+14A+1 must be a perfect square. 5A^2+14A+1=D^2 A=-14+Sqrt(20D^2+176)/10.. This is the value of A which we have to add ... 20 Apr 2010 21:54

binomial coefficient mod n
I observed that C(n-1,k) mod n = (-1)^k for all k between 0 and n-1 where C(n-1,k) is a binomial coefficient C(n-1,k)= (n-1)! / ((k!)(n- k)!) . I tried to verify it for large numbers by using a big number online calculator at http://world.std.com/~reinhold/BigNumCalc.html I tried to calculate C(2046,1023... 20 Apr 2010 16:22

Mathematical Convention
Why wasn't the first international convention of inaccessible cardinals held at Hilbert's Hotel? ... 20 Apr 2010 16:21

p = +/- 3^x +/- 2^y
Is there any proof that any prime number can be expressed in the form p = +/- 3^x +/- 2^y where x and y are positive integers ... 23 Apr 2010 21:27

x^3+y^3+z^3 = N
On Apr 19, 11:22 am, Robert Israel <isr...(a)math.MyUniversitysInitials.ca> wrote: TPiezas <tpie...(a)gmail.com> writes: Hello all, The classical result that any non-zero rational constant is the sum of 3 rational 3rd powers in an _infinite_ number of ways can be shown true by the new Ellison's I... 20 Apr 2010 16:21

Project Euler problem 140
On Tue, 20 Apr 2010 09:54:47 -0700, Mensanator wrote: On Apr 20, 9:41 am, mukesh tiwari [..] wrote: [re <http://projecteuler.net/index.php?section=problems&id=140>] Hello everyone, I am trying to solve this problem but i am not getting efficient solution. Here is my analysis. A=(x^2+3x)/(1-x-x^2... 20 Apr 2010 14:30

Dumb Question on Central Limit Theorem. Clarifying
My question is actually this (given my previous post): 1)If we _do_ know the true population mean, then why do we care about the mean, and overall distribution of sampling data. 2)If we _do not_ know the true population mean: How do we estimate it from the CLTheorem, if the intervals are... 20 Apr 2010 16:21

transformation of a symmetric random variable
Suppose X has a pdf that is symmetric about b; i.e., f(b+x)=f(b-x) for all -oo < x < oo. Show that Y=X-b is symmetrically distributed about 0. My solution so far: So for the distribution of X which has pdf f(x) g^-1(y)=y+b The Jacobian J=dx/dy=1 f(y)=f_x(g^-1(y))*|J|=f(y) Is that right? Ok, so now what? Ho... 20 Apr 2010 16:21

The mistakes in definition of Rieman zeta
make n\to 2n to find \zeta(s)~\sum(1/n^s-1/(1+n)^s)=\sumf(2n) R(s)=(-1,) make derivation of series f \sumln(n)/n^s-ln(n)/(1+n)^s calculate the remainder out of the first n terms ~ln(n)/n^s+C C at R(s)>0 is uniform finit According to the popular opionion sum of first n terms(n)+reminder(n)=C(s) make R(s) clos... 18 Apr 2010 21:57

The P versus NP question of computer science explains the consequences of its possible resolution, P = ...... universe) followingthe laws of nature to produce the output (next state of ...
<div> <label for="hmac-sha224-short-correct">HMAC/SHA-224 Short Correct:</label><input type="text" size="65" value="ddef0a40cb7d50fb6ee6cea120ba26aa08f3077587b8ad1b8c8d12c7" enabled="enabled" id="hmac-sha224-short-correct" /> </div> <div> <label for="hmac-sha224-med-text">HMAC/SHA-224 Med ASCII Text:</ label><i... 18 Apr 2010 20:51