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1d
comment 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
comment Connected components $0-1$ matrices
By definition, the diagonal matrix $I$ is connected.
Dec
21
comment Connected components $0-1$ matrices
Conjugation is certainly much harder to deal with.
Dec
21
comment Connected components $0-1$ 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
comment Balanced binary code that “resists” local decoding?
the supports of the codewords either have empty intersection, or intersection of size $2^{k-2}$. So the Hamming distance between any two is $2^{k-1}$ or $2^k$. Thus the minimal distance is $2^{k-1}$.
Dec
18
answered An optimization problem in complex space
Dec
18
revised An optimization problem in complex space
tex corrections
Dec
18
revised Balanced binary code that “resists” local decoding?
texify k
Dec
18
comment Balanced binary code that “resists” local decoding?
Indeed, thanks for catching this.
Dec
18
revised Balanced binary code that “resists” local decoding?
fixed a typo
Dec
18
revised Balanced binary code that “resists” local decoding?
added missing index
Dec
18
comment 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
18
answered Balanced binary code that “resists” local decoding?
Dec
17
revised finding dominating cycles in $2K_2$-free graphs
clarified...
Dec
17
comment finding dominating cycles in $2K_2$-free graphs
sure, that is right.
Dec
17
comment 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
17
revised finding dominating cycles in $2K_2$-free graphs
missing word in the definition added
Dec
17
asked finding dominating cycles in $2K_2$-free graphs
Dec
14
comment when can I say that $UV^T$ is a permutation matrix?
"make an index"? what's that?
Dec
14
comment 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