1,681 reputation
723
bio website
location Kaiserslautern, Germany
age 27
visits member for 4 years, 1 month
seen Dec 15 at 20:00

I am a PhD student at the Algorithms & Complexity group at University of Kaiserslautern, Germany. I research design and analysis of parallel algorithms and data structures.

In my free time I read books, enjoy (and sometimes make) music, code, work out and roam the webs.


You can find sources for all self-created images I post on Stack Exchange here.


Dec
15
awarded  Caucus
Dec
3
comment Matlab wrong cube root
FWIW, this is not (solely) a Matlab issue. Mathematica does the same: N @ (-1)^(1/3) → 0.5 + 0.866025i but CubeRoot[-1] → -1.
Nov
21
comment tensor product and composition (in monoidal category)
This indeed seems to be a pure mathematics question; migrating.
Nov
20
comment A number theoretical problem
This is a pure mathematics question without any obvious relation to CS (despite being part of a foundational mathematics curriculum for CS students). Hence, it belongs on Mathematics; I'm migrating it now.
Nov
20
comment Estimating the $\beta$th moment of a uniform random variable
This is a pure mathematics question without any obvious relation to CS (despite being part of a foundational mathematics curriculum for CS students). Hence, it belongs on Mathematics; I'm migrating it now.
Nov
9
awarded  Yearling
Sep
30
awarded  Explainer
Sep
17
comment All pairs shortest path in undirected and unweighted graphs
FWIW, nowadays questions such as this are ontopic on Computer Science.
Aug
8
comment Question concerning a list sorting problem
Crossposted to cs.SE.
Aug
1
comment Why does convolution not maintain asymptotic equality of coefficients?
Hm, I note that $g$ does not seem to be algebraic; $[z^n]\frac{\mathrm{Li}_2(cz)}{cz} = \frac{c^n}{(n+1)^2}$. It may be worthwhile to investigate convolutions of only algebraic generating functions.
Jul
31
comment Do asymptotically equivalent coefficients survive convolution at least in Θ?
I was able to solve the issue in my special application case by 0) picking a simple $L_B$ (OGF $(1-dz)^{-1}$), 1) applying the definition of $\sim$ and $\lim$ subsequently and 2) choosing a generous $\varepsilon$ for the lower bound. We indeed have $\Theta$-equality of the convolution's coefficients in this case.
Jul
31
comment Lower bound for a relative of the central binomial coeff
Huh. In the partial fraction expansion the denominator $1-4z-z^2$ occurs which has that zero; apparently its contribution cancels out. My bad. Anyway, I don't see how to get to strict lower bounds from an asymptotic so asymptotic singularity analysis (at least as far as I know it) it out of the question.
Jul
31
awarded  Curious
Jul
30
comment Lower bound for a relative of the central binomial coeff
Since the dominant singularity is at $-2 + \sqrt{5}$ you have $T(2m,m) \sim (2+\sqrt{5})^n \cdot \dots$, so a(ny) lower bound of order $4^m$ from some moderately sized $m$ on seems likely, yes.
Jul
30
comment Do asymptotically equivalent coefficients survive convolution at least in Θ?
In my application, I have $\rho < 1$ (since the languages usually grow exponentially; the others are (probably) boring). If a proof is easier for $\rho = 1$ but extends to smaller $\rho$, go ahead. (I lack the knowledge/skill to see what impact that can have.)
Jul
30
revised Do asymptotically equivalent coefficients survive convolution at least in Θ?
added 30 characters in body
Jul
30
accepted Expectation of maximum of a function whose expectation is concave
Jul
30
comment Why does convolution not maintain asymptotic equality of coefficients?
Since this goes well beyond the question as posed, I decided to write up the follow-up question as per your gut feeling. Thanks for thinking about this!
Jul
30
asked Do asymptotically equivalent coefficients survive convolution at least in Θ?
Jul
30
accepted Why does convolution not maintain asymptotic equality of coefficients?