bio  website  math.ubc.ca/~israel 

location  Vancouver BC  
age  64  
visits  member for  4 years, 5 months 
seen  17 hours ago  
stats  profile views  6,060 
Associate Professor Emeritus, University of British Columbia, and Optimization Algorithms Researcher, DWave Systems, Burnaby BC
1d

awarded  Nice Answer 
1d

comment 
Which polynomial's roots are its coefficients?
Wrote out the equations, and solved in Maple. 
1d

comment 
Which polynomial's roots are its coefficients?
Perhaps you mean $x^2 + x  2$ instead of $x^2  2 x$, and $x^3+x^2x1$ instead of $x^3x^2x$, and excluding those where $0$ is a root. 
1d

answered  Which polynomial's roots are its coefficients? 
2d

answered  Simplifying a Taylor polynomial that involves Stirling numbers of the second kind 
2d

comment 
Simplifying a Taylor polynomial that involves Stirling numbers of the second kind
You certainly wouldn't have just $a^n$ in the $x^n$ term. For example, for $n=2$, $$\sum_{m=1}^2 (1)^{m1} (m1)! S(2,m) a^m = a  a^2$$ 
2d

comment 
Perturbed Chebyshev polynomials
Related to what @JoeSilverman wrote, $T_n(\cos \theta) = \cos(n \theta)$. You could define for noninteger $\alpha$, $T_\alpha(z) = \cos(\alpha \arccos(z))$, an analytic function on the complement of the branch cuts for $\arccos$. 
Aug
31 
comment 
Perturbed Chebyshev polynomials
$T_n$ and $f_n$ are polynomials of degree $n$. Is your $T_{\alpha_n}$ supposed to be a polynomial, and if so of what degree? 
Aug
31 
comment 
Decomposition of orthogonal matrix into 2 orthogonal matrices
For any orthogonal matrix $P$, take $Q = A^{1} P$. 
Aug
29 
awarded  Nice Answer 
Aug
28 
answered  May integration spoil realanalyticity? 
Aug
19 
revised 
when does elementwiselog preserve positivesemidefiniteness?
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Aug
18 
answered  when does elementwiselog preserve positivesemidefiniteness? 
Aug
14 
answered  How many rearrangements must fail to alter the value of a sum before you conclude that none do? 
Aug
12 
comment 
Solving a nonlinear PDE numerically
Initial value ODE problems may be easier than boundary value problems. But e.g. in Maple's dsolve you don't generally need to guess an approximate solution. 
Aug
11 
answered  How can I show that “almost all function” have property P? 
Aug
11 
comment 
Maximal Number of Pairs of Orthogonal vectors in a set of $n$ vectors in $\mathbb{R}^3$
@OlegEroshkin: You're getting $n^3/9$ pairs from $n$ vectors? I don't think so. 
Aug
11 
comment 
Maximal Number of Pairs of Orthogonal vectors in a set of $n$ vectors in $\mathbb{R}^3$
Why is that not permitted? 
Aug
11 
comment 
Version of Stone Weierstrass for functions not vanishing at infinity
Again, all continuous functions on $\mathbb R^n$ are continuous functions of bounded smooth functions, since $x_j = \tan(\arctan(x_j))$ and $\tan$ is continuous on $(\pi/2, \pi/2)$. 
Aug
11 
revised 
Solving a nonlinear PDE numerically
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