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location  Oxford, United Kingdom  
age  51  
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7h

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Which universities teach true infinitesimal calculus?
perhaps "rigorous" or "axiomatic" would be better word than "true". 
2d

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symmetrizability of generalised cartan matrix
either wikipedia is wrong, or this is by definition: en.wikipedia.org/wiki/Cartan_matrix en.wikipedia.org/wiki/Symmetric_matrix#Symmetrizable_matrix 
Dec 21 
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Connected components $01$ matrices
By definition, the diagonal matrix $I$ is connected. 
Dec 21 
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Connected components $01$ matrices
Conjugation is certainly much harder to deal with. 
Dec 21 
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Connected components $01$ matrices
do you require simultaneous permutations of rows and columns (i.e. conjugation by a permutation matrix)? Or you allow different permutations to permute rows and columns? 
Dec 19 
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Balanced binary code that “resists” local decoding?
the supports of the codewords either have empty intersection, or intersection of size $2^{k2}$. So the Hamming distance between any two is $2^{k1}$ or $2^k$. Thus the minimal distance is $2^{k1}$. 
Dec 18 
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Balanced binary code that “resists” local decoding?
Indeed, thanks for catching this. 
Dec 18 
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Balanced binary code that “resists” local decoding?
there is a discrepancy in the definition of $k$ vs examples; e.g. your 1st example corresponds to $k=1$, according to your definition. 
Dec 17 
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finding dominating cycles in $2K_2$free graphs
sure, that is right. 
Dec 17 
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automorphism of prime order for group of Lie type in
You can have a look at the "Atlas of finite groups" by J.Conway et al., which has a lot of info on $O_8^+(\mathbb{F}_3)$. 
Dec 14 
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when can I say that $UV^T$ is a permutation matrix?
"make an index"? what's that? 
Dec 14 
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finding permutation matrix I which minimizes TRACE( I* C*( I^T)* D) matrix
you might like to check out arxiv.org/abs/1403.7721 for up to date references etc 
Dec 14 
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finding permutation matrix I which minimizes TRACE( I* C*( I^T)* D) matrix
i.e. instead of n! permutations you might still need to check something like $2^n$ of them. 
Dec 14 
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finding permutation matrix I which minimizes TRACE( I* C*( I^T)* D) matrix
well, there was a lot of research done on this problem. it would not be necessary to check a fraction of all permutations of n symbols, but still nobody knows how to check less than exponentially (in terms of n) many of them. 
Dec 12 
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Dihedral subgroups of $\mathrm{PSL}_2(\mathbb{F}_q)$
IMHO this is already in L.Dickson's book "Linear Groups", which was reprinted by Dover in 1958. 
Nov 15 
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Can any bounded area defined by polynomial inequality in $\mathbb{R}^n$ be partitioned into simply connected finite area such that
it is wellknown that any semialgebraic set can be triangulated. The question you ask seems like a particular case of this fact. 
Oct 24 
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A number array related to colored necklaces and the primes
A059966 features a reference to a paper by me, and in fact I am wellaware of this relation. :) 
Oct 23 
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A number array related to colored necklaces and the primes
although I don't see an immediate connection. 
Oct 23 
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A number array related to colored necklaces and the primes
oeis.org/A001037 is another related sequence, although a 
Oct 16 
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Is there an English translation of Minding's 1839 paper?
Assuming it's no coincidence that you have a Dutch name, you certainly can read German without needing to look in a dictionary too much; just try;) The harder part will be to convert the text to modern terminology, but this equally applies to other languages. 