bio  website  mathematik.uniwuerzburg.de/… 

location  Würzburg  
age  49  
visits  member for  3 years, 8 months 
seen  47 mins ago  
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I'm a professor of mathematics at the University of Würzburg (Germany). For further infos see my web page.
1d

comment 
Need explicit formula for certain “$q$numbers” involving gcd's
@OP: What is $\langle e_0,e_0\rangle$? It seems to me that the problem is not well formulated, as $gcd(0,0)=\infty$. In particular, I don't know how to interpret your assertion $0=\langle o_0,o_1\rangle=\langle e_0,e_1qe_0\rangle=qq\cdot q^{gcd(0,0)}$. 
Jun 21 
comment 
How to prove this polynomial always has integer values at all integers?
Comparing the leading coefficient of $P_m(x)$ with that of $\binom{x}{2m}$, one gets that $\frac{3}{(2m+1)(m1)}\binom{2m}{m}\sum_{i=0}^m\binom{m}{i}^2\frac{1}{2i1}$ is an integer provided that $P_m(\mathbb Z)\subseteq\mathbb Z$. Is this integrality known? I don't know if there is a closed expression for the sum. 
Jun 8 
comment 
Existence of polynomials of degree $\geq 2$ which represent infinitely many prime numbers
@Gerhard Paseman: $x^2+y^2$ even assumes all the infinitely many primes in $4\mathbb N+1$ ... 
Jun 8 
comment 
Existence of polynomials of degree $\geq 2$ which represent infinitely many prime numbers
@Yaakov: Doesn't that imply that one of the finitely many polynomials represents infinitely many primes ...? 
Jun 8 
answered  Existence of polynomials of degree $\geq 2$ which represent infinitely many prime numbers 
May 26 
awarded  Necromancer 
May 26 
revised 
Seeking conceptual explanation of these nice bijections on roots of unity
fixed typos 
May 26 
answered  Seeking conceptual explanation of these nice bijections on roots of unity 
May 19 
comment 
What is prime power of this equation of p?
@darya: Instead of asking a new question in a comment, you probably should pose this as another question. Also, you should tell why you are interested in this specific equation. 
Apr 9 
revised 
Is there a nonexplicit characterization of the Specht modules?
fixed two typos 
Mar 16 
answered  Invariant subspaces of an $F_2$representation of the affine linear group of dimension 1 
Mar 10 
answered  Permutation polynomials mod $p$ of the form $(x+1)^nx^n$ 
Feb 28 
comment 
If d(“G/H”) < d(G) = 2, must H contain a primitive element?
@Pablo: Indeed, my comment wasn't correct. Now that Derek Holt provided the details, there is no need to fix it. 
Feb 26 
awarded  Good Answer 
Feb 26 
revised 
Circles and rational functions
added 248 characters in body 
Feb 26 
revised 
Circles and rational functions
improved the answer, provided a link to a preprint with more details 
Dec 27 
answered  Measuring how closely a missing projective plane can be approached by an equivalent structure 
Dec 17 
awarded  Enlightened 
Dec 17 
awarded  Nice Answer 
Dec 4 
comment 
A generalized meanvalue theorem
By stated result I meant the OP's $3$point version, not the one from your answer which is a different formulation of the Schwarz version. 