Per Alexandersson

Zurich, Switzerland

www2.math.su.se/~per

Age: 28

Currently interested in Schur functions and semistandard Young tableaux and misc. related representation theory and combinatorics.

Phd thesis defended 2013, titled Combinatorial Methods in Complex Analysis.

I keep an eye out for interesting results related to complex dynamics, computability, and computer-assisted research. I use Mathematica extensively in my research. My other main programming languages are Java, LaTeX, PHP, C, etc.

May
19
comment Character sums over a fixed subset of skew tableaux
The closest thing might be some sort of interpretation in terms of Shifted Schur functions, see (0.14) in arxiv.org/pdf/q-alg/9605042v1.pdf after some suitable scaling (perhaps divide both sides with $f_\lambda$?).
May
18
comment Counting ways to Arrange Variable Sized Objects into Fixed Number of Spaces
This is a bit poorly formulated: as I see it, the sum of the size of your objects is 1+2+...+i.
May
15
reviewed Approve suggested edit on Expressing adj(A) as a polynomial in A?
May
15
comment A Bernstein-like Combinatorial Sum
Hm, maybe that's the expression OP started with...
May
15
reviewed Approve suggested edit on Weak solutions for a PDE of fourth order
May
15
answered Important open problems that have already been reduced to a finite but infeasible amount of computation
May
15
comment Simplex in convex polytope, pulling triangulation
@FranciscoSantos: Ok, so every k-dim simplex should have at least one $k-1$-dimensional face which is not in the interior of $P$.
May
12
answered Contest problems with connections to deeper mathematics
May
12
comment Least collaborative mathematician
I wonder if he also has most pages as single author... I see several 5-7-pages papers om MathSciNet.
May
6
revised Combinatorial definition of Hall–Littlewood polynomials (sum over SSYT?)
added 157 characters in body
May
6
comment Combinatorial definition of Hall–Littlewood polynomials (sum over SSYT?)
It depends what you mean by explicit; You can easily write this as a sum over a family of tableaux, with some not-so-difficult combinatorial statistics on said tableaux.
May
6
comment Is there a simple description of this group?
Perhaps change the title to something more descriptive?
May
5
comment Combinatorial polynomials from general diagram fillings?
Yeah, I was thinking about those, but most sources I have found only deal with Ferres shapes. Is there a source with more general arrangements?
May
5
comment Combinatorial polynomials from general diagram fillings?
Ah, that's a very interesting reference!
May
5
reviewed Approve suggested edit on Appropriate BCs of First Order Hyperbolic Semi-Linear Equation
May
5
asked Combinatorial polynomials from general diagram fillings?
May
5
comment Automatically highlight words from a predefined list
Yes, it is similar; however, all solutions presented there require extra software or that one manually mark all instances where one wants to do some highlightning
May
4
comment Dimension of the span of all partial derivatives of a given symmetric polynomial $f$ and the polynomial $E(f)$
Can you please provide a bit more background? Where does this problem appear?
May
4
reviewed Approve suggested edit on Extensions of $SL(2,\mathbb{F}_q)$
May
4
answered Combinatorial definition of Hall–Littlewood polynomials (sum over SSYT?)
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