11,835 reputation
11638
bio website math.bgu.ac.il/~gulkod
location Beersheba, Israel
age 27
visits member for 3 years, 6 months
seen Aug 15 at 10:03

I'm a Ph.D. student at Ben-Gurion University of the Negev, Beer-Sheva, Israel.
My research interests include algebraic groups in general and linear groups in particular, representations of groups - in particular highly and sharply transitive representations.


Aug
4
awarded  Nice Answer
Jul
17
comment Find $R$ such that $\sum\limits_{n=2k}^{3k}\binom{3k}{n}\cdot{(R)}^n\cdot{(1-R)}^{3k-n}$ is constant for all $k\in\mathbb{N}$
I guess it's a trivial suggestion, but did you look at $$1=(R+(1-R))^{3k}=\sum_{n=0}^{3k}\binom{3k}{n}R^n(1-R)^{3k-n}$$ Then you can denote $$B_k=\sum_{n=k}^{2k}\binom{3k}{n}R^n(1-R)^{3k-n}, \hspace{5pt}C_k=\sum_{n=0}^{k}\binom{3k}{n}R^n(1-R)^{3k-n}$$ And then $A_k+B_k+C_k=1$. I'm not sure it leads anywhere, but seems like a good place to start from. $A_k$ and $C_k$ look symmetric in a way.
Jul
10
answered The best way to factorize?
Jul
9
comment Show $f(t) = t$ given $\int_0^1 t^n f(t) dt = \frac{1}{n+2}\quad \forall n\in\mathbb{N}.$
Then - it seems correct!
Jul
9
comment Show $f(t) = t$ given $\int_0^1 t^n f(t) dt = \frac{1}{n+2}\quad \forall n\in\mathbb{N}.$
What is your question?
Jul
9
reviewed Reopen Are NSA Mathematicians second-rate?
Jul
6
reviewed Reviewed Limits of $\frac{1+\cos\theta}{\sin^2\theta}$
Jul
6
comment Limits of $\frac{1+\cos\theta}{\sin^2\theta}$
I edited it they way it seemed reasonable for me. Can you please elaborate on what do you know what you tried ("factor it" - what does it mean?)
Jul
6
revised Limits of $\frac{1+\cos\theta}{\sin^2\theta}$
added 100 characters in body; edited title
Jul
5
accepted Closed form of $\sum_{k=0}^nk\binom{k}{3}\binom{2n}{k}$
Jul
5
comment Closed form of $\sum_{k=0}^nk\binom{k}{3}\binom{2n}{k}$
Thanks, that solves it!
Jul
5
comment Closed form of $\sum_{k=0}^nk\binom{k}{3}\binom{2n}{k}$
How did you get the last equality?
Jul
5
asked Closed form of $\sum_{k=0}^nk\binom{k}{3}\binom{2n}{k}$
Jul
2
awarded  Curious
Jun
18
comment Need some help with this integral
Why don't you want to use partial fractions?
Jun
12
reviewed Approve suggested edit on Why does one modulus disappear when modded by another modulus?
Jun
12
reviewed Leave Closed Some questions on Nilpotent matrix
Jun
9
answered Show that $(\sqrt{2} + \sqrt{3})^{2009}$ is rounded to an even number.
Jun
8
comment Solving $X+X^T=tr(X)M$
I guess that the matrix $M$ is given!
Jun
8
comment Hints in a linear combination
Right, so what is definition of $U$ being a linear combination of $V,W$?