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Dec
14
comment 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
13
answered finding permutation matrix I which minimizes TRACE( I* C*( I^T)* D) matrix
Dec
12
comment 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.
Dec
9
reviewed Approve Real-world applications of mathematics, by arxiv subject area?
Nov
26
awarded  Yearling
Nov
25
awarded  Revival
Nov
15
comment Can any bounded area defined by polynomial inequality in $\mathbb{R}^n$ be partitioned into simply connected finite area such that
it is well-known that any semialgebraic set can be triangulated. The question you ask seems like a particular case of this fact.
Nov
9
answered Polynomial-time algorithm for determining whether a polynomial is positive on $\mathbb{N}$
Oct
28
reviewed Approve Minimize distance between centroids of subsets of points
Oct
24
comment A number array related to colored necklaces and the primes
A059966 features a reference to a paper by me, and in fact I am well-aware of this relation. :-)
Oct
23
comment A number array related to colored necklaces and the primes
although I don't see an immediate connection.
Oct
23
comment A number array related to colored necklaces and the primes
oeis.org/A001037 is another related sequence, although a
Oct
16
comment 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.
Oct
16
comment For a Sum-of-Squares cost functions J(x) is it true that J(x)-j* is also SOS?
oh, I just meant to say that in nonlinear least squares the structure of the problem is similar to yours. (And nonlinear least squares have received a lot of attention...)
Oct
14
comment Thinnest 2-fold coverings of the plane by congruent convex shapes
this is about teh case when only translations are allowed: link.springer.com/article/10.1007/s00493-012-2860-3
Oct
14
comment For a Sum-of-Squares cost functions J(x) is it true that J(x)-j* is also SOS?
Nonlinear least squares problems have this kind of structure. en.wikipedia.org/wiki/Non-linear_least_squares
Oct
14
revised For a Sum-of-Squares cost functions J(x) is it true that J(x)-j* is also SOS?
nothing to do with group theory IMHO
Oct
14
revised For a Sum-of-Squares cost functions J(x) is it true that J(x)-j* is also SOS?
added 70 characters in body
Oct
14
revised For a Sum-of-Squares cost functions J(x) is it true that J(x)-j* is also SOS?
a typo
Oct
14
comment For a Sum-of-Squares cost functions J(x) is it true that J(x)-j* is also SOS?
it works for a different dehomogenesation, cf. my edited answer.