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2d
comment name for a polytope constructed from a system of linear equations?
I must say I don't recall details right now - I was computing something generalising triangulations, using 4t2.
Mar
26
comment How to pack 3D boxes into a bigger box?
dynamic programming might work well on instances which are not too big, IMHO
Mar
26
comment The maximal eigenvalue of a symmetric Toeplitz matrix
I take this back: from mathoverflow.net/questions/68099/… it is seen that apparently for $n\geq 9$ there cannot be an explicit formula.
Mar
25
comment What is wrong with the argument that zero permanent is polynomial?
my understanding is that there is no good formula for permanent...
Mar
24
comment Dissolution of Tensors
When I voted to close this, it looked to me as a very vague question in terribly broken English... I've retracted my vote.
Mar
23
comment Matrix Elements of Real Representations
you might like to investigate what $T$ does to these invariant forms (it should map the one for $\rho$ to the one for $\overline\rho$ --- or perhaps the other way around...)
Mar
22
comment algorithm of polytope
well, it would make sense to add vertices one by one...
Mar
21
comment Reference for multivariate orthogonal polynomials
you might then accept my answer (hint, hint :))
Mar
18
comment Nauty software package and weighted graphs
There is no such command in dreadnaut. You will have to supply it the already prepared non-weighted graph.
Mar
18
comment Nauty software package and weighted graphs
Well, how you represent weights is an entirely different question. In the setting of computing automorphisms and isomorphisms all what matters is that different weights are represented by different integer numbers (or colours).
Mar
17
comment Computing Voronoi poles in $\mathbb{R}^d$ (the farthest points within each cell)
For each cell, you seem to need to maximize a convex quadratic function on it. This surely cannot be easy in general.
Mar
16
comment Parodies of abstruse mathematical writing
In particular given the recent work on HOTT, the title of that paper does not sound silly...
Mar
11
comment Computer software for periods
Ah, right. So this looks like that in the end one will get the integral of a rational function over a triangle, which is, conjecturally, identically 0.
Mar
11
comment Computer software for periods
Right. I guess such mysteries are not possible in case one has a "nice" (here: affine) map between domains of integration. Perhaps Kontsevich-Zagier knew this already.
Mar
11
comment Computer software for periods
OK, so the RHS is a period over certain 4-gon, lying above the $x$-axis?
Mar
11
comment Computer software for periods
How about absolute convergence (a requirement in the definition of a period) of your double integrals on respective triangles? Is it obvious?
Mar
11
comment Computer software for periods
oops, sorry. It's $\sqrt{21}-5$. I need better glasses. By the way: integrating polynomials over simplices is just differentiation (of the Laplace transform). One might be tempted to say that same holds for rational functions (which will need to be expanded...). I don't know if this is correct though (convergence is not obvious...).
Mar
11
comment Computer software for periods
is there a reason that one log has ||, while the other has not?
Mar
11
comment Experimenting with the spider relator
Should be easy to check, I suppose.
Mar
10
comment An infinite sum which approaches a geometric series
In the integral, I'd try to replace the part that causes the absence of a "nice" form by a simpler upper bound, e.g. taking first few terms of the Taylor expansion.