bio | website | cs.ox.ac.uk/people/… |
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location | Oxford, United Kingdom | |
age | 51 | |
visits | member for | 4 years |
seen | 16 hours ago | |
stats | profile views | 1,832 |
Aug 8 |
answered | Possible degrees of faithful projective representations of $\mathrm{PSL}(k,q)$ and $\mathrm{Sp}(2k,q)$ over complex numbers |
Aug 8 |
comment |
Possible degrees of faithful projective representations of $\mathrm{PSL}(k,q)$ and $\mathrm{Sp}(2k,q)$ over complex numbers
The poster most probably doesn't have access to Magma. (well, the same computations can be done in GAP (gap-system.org), which is free...) |
Aug 6 |
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When polynomial GI implies polynomial (edge) colored GI?
other questions are harder :) |
Aug 6 |
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When polynomial GI implies polynomial (edge) colored GI?
the explicit generators are trivial to find. Indeed, the action on the degree 2 vertices is just the action of $S_n$ on pairs {[12],[13],..,[pq]...}, for p<q. |
Aug 6 |
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When polynomial GI implies polynomial (edge) colored GI?
Actually if you read details in A052565 you'll see that it is n! for n>3. |
Aug 6 |
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When polynomial GI implies polynomial (edge) colored GI?
The case $n=3$ is exceptional, as the resulting graph is hexagon, so you get 12. Then for all $n\geq 4$ you should just get $n!$. |
Aug 6 |
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When polynomial GI implies polynomial (edge) colored GI?
OK; then please write "the subdivision", not just "subdivision". Anyhow, I am sure that the automorphism group of such a graph is easy to describe for any $n$. (not sure though what you mean by "tractable to compute" - by some particular algorithm? Or do you mean "describe"?) |
Aug 6 |
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When polynomial GI implies polynomial (edge) colored GI?
Do you mean a particular subdivision of $K_n$? (I have trouble reading English with missing articles). In your description, you seem to have defined a family of subdivisions for a given $n$, not just one particular. |
Aug 6 |
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When polynomial GI implies polynomial (edge) colored GI?
How is A052565 relevant here? What are these numbers counting? |
Aug 5 |
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Software tools for medium-scale systems of polynomial equations
yes, I agree that it's quite probable that the exact original polynomials have a common real 0. IMHO trying numerical methods to improve upon 2*10^-9 is pretty much pointless here. |
Aug 5 |
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Software tools for medium-scale systems of polynomial equations
SQP most probably will terminate in a local minimum. I'd be surprised if any restarts from such a minimum are attempted. |
Aug 4 |
answered | Software tools for medium-scale systems of polynomial equations |
Aug 3 |
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Software tools for medium-scale systems of polynomial equations
as you have a sum squares cost function to optimise, I suppose the most natural method will be one based on semidefinite programming (a.k.a. Lasserre hierarchies). Did you try these? |
Aug 3 |
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Software tools for medium-scale systems of polynomial equations
your link does not seem to work; it leads to the URL raw.githubusercontent.com/alexflint/polygamy/master/out/… which does not show up. |
Jul 31 |
accepted | centralizer of the order 2^k cyclic permutation matrix over F_2 |
Jul 31 |
answered | centralizer of the order 2^k cyclic permutation matrix over F_2 |
Jul 31 |
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Smallest Connected Graph for Given Degree Sequence
ok, i edited the question as to make it clear here. |
Jul 31 |
revised |
Smallest Connected Graph for Given Degree Sequence
english fix |
Jul 31 |
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Smallest Connected Graph for Given Degree Sequence
ok, but what are you minimizing? |
Jul 31 |
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Smallest Connected Graph for Given Degree Sequence
I don't understand. The number of vertices and the number of edges are already GIVEN! |