126,195 reputation
583217
bio website math.ubc.ca/~israel
location Richmond, Canada
age
visits member for 3 years, 5 months
seen 12 hours ago

I'm an Emeritus Associate Professor of Mathematics at University of British Columbia and an Optimization Algorithms Researcher at D-Wave Systems in Burnaby BC


1d
comment Count the integers between $20000$ and $30000$ that end in $39$, and end in $33$ in base $4$, and end in $37$ in base $8$
The last two digits of $x$ in base $b$ are $d_1, d_0$ where $x = d_0 + b d_1 + b^2 (\ldots)$, i.e. $x \equiv d_0 + b d_1 \mod b^2$.
1d
answered Find $n$ between $100$ and $1000$ so that $2^n+2$ is divisible by $n$
1d
answered Count the integers between $20000$ and $30000$ that end in $39$, and end in $33$ in base $4$, and end in $37$ in base $8$
1d
comment Probability that the red fish are the first species to become extinct
Why do you think these arrangements are not counted? They are certainly included in the event "the last fish is green and the last non-green fish is blue".
2d
answered Probability that the red fish are the first species to become extinct
2d
comment Proof that Every Positive Operator on V has a Unique Positive Square Root
The proof is not that trivial.
2d
answered Proof that Every Positive Operator on V has a Unique Positive Square Root
2d
comment IMPROPER INTEGRAL of euler formula
No, it is completely wrong.
2d
revised Is there an easier way to find $\frac{d^9}{dx^9}(x^8\ln x)$ than using the product rule repeatedly?
added 306 characters in body
2d
answered Is there an easier way to find $\frac{d^9}{dx^9}(x^8\ln x)$ than using the product rule repeatedly?
2d
comment Power series function expansion as solution for integral equation
You might look at en.wikipedia.org/wiki/Perturbation_theory
2d
answered Why does the $\tan$ reduction formula have a restriction?
2d
answered Simplifying nested/complex fractions with variables
2d
revised Counting antichains in the limit $n \rightarrow \infty$.
deleted 13 characters in body
2d
revised Counting antichains in the limit $n \rightarrow \infty$.
added 566 characters in body
2d
answered Trigonometric equation for double angle
2d
answered Counting antichains in the limit $n \rightarrow \infty$.
2d
answered A question about moment-generating function
2d
answered Power series function expansion as solution for integral equation
2d
comment Prove if n<m there is at least one [(n/m)]?
$\lceil n/m \rceil$