22,036 reputation
1961
bio website math.ubc.ca/~israel
location Vancouver BC
age 64
visits member for 4 years, 4 months
seen 9 hours ago
Associate Professor Emeritus, University of British Columbia, and Optimization Algorithms Researcher, D-Wave Systems, Burnaby BC

2d
comment Minimal number of intersections in a convex $n$-gon?
For $n=9$ I get $124$ for the parabola as opposed to $126$ for the regular nonagon.
Jul
24
answered Existence of a countable linear combination with positive coefficients
Jul
21
comment “Forthcoming paper” of Goldston-Graham-Pintz-Yıldırım
You can search arXiv... arxiv.org/find/math/1/au:+Yildirim_C/0/1/0/all/0/1
Jul
21
awarded  Explainer
Jul
21
revised Lipschitz-like behaviour of quartic polynomials
Typo correction
Jul
20
comment Distribution of bounded summation of i.i.d random variables
I prefer to write multiple integrals "physics style" with the $d$(variable)'s after the integral sign rather than at the end. It helps to make the connection between variables and endpoints clearer.
Jul
19
comment Distribution of bounded summation of i.i.d random variables
$x$? What $x$? It's a function of $s$ and $T$
Jul
17
answered Determining when combinatorial sums are zero
Jul
17
comment Determining when combinatorial sums are zero
Your numbers seem to be not $a_n$ as you defined it but $a_n/n!$. Of course that doesn't affect the signs.
Jul
13
comment Measure-minimizing simplex with fixed inradius
Also nonunique for a measure supported in the open ball of radius $r$, or for one supported outside the closed ball of radius the circumradius of the regular $n$-simplex of inradius $r$.
Jul
10
comment Distribution of bounded summation of i.i.d random variables
For one thing, there's no reason for $E[K]$ to be an integer.
Jul
10
comment Distribution of bounded summation of i.i.d random variables
No, but in the limit as $T \to \infty$ you have the Elementary Renewal Theorem.
Jul
9
comment Distribution of bounded summation of i.i.d random variables
1) memoization. 2) Thats why it's a sum over $n$ rather than an integral. 3) Because $S_n = S_{n-1} + X_n$.
Jul
9
revised Distribution of bounded summation of i.i.d random variables
added 232 characters in body
Jul
9
answered Distribution of bounded summation of i.i.d random variables
Jul
8
answered SO(3) transformation that produces a reflection
Jul
7
revised Square Integrable Harmonic Functions in an Infinite Strip
added 157 characters in body
Jul
7
revised Square Integrable Harmonic Functions in an Infinite Strip
deleted 18 characters in body
Jul
7
answered Square Integrable Harmonic Functions in an Infinite Strip
Jul
7
comment Is $f(x,y)=\sum_{n\in\mathbb{Z}\backslash\{0\}}\frac{1}{n}e^{2\pi i(xn+yn^2)}$ essentially bounded?
Why not? The set of $(x,y)$ such that the series fails to converge is measurable and its intersection with every line $y = constant$ has measure $0$, therefore that set has $2$-dimensional measure $0$.