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 Apr 3 comment A Conjecture based on the Complex Conjugate Root Theorem. I agree, I was just thinking aloud Apr 3 comment A Conjecture based on the Complex Conjugate Root Theorem. so you can get polynomials of degree n with n prescribed roots... Apr 3 comment A Conjecture based on the Complex Conjugate Root Theorem. every monic polynomial f(z) is the product of $z-\alpha_k$, where $\alpha_k$ are its roots. Mar 5 comment On Hyper-geometric Functions and its recurrence relation right, just replace $a$ by $a+n$ Mar 5 comment On Hyper-geometric Functions and its recurrence relation $a$ is just a parameter; nothing will become invalid if you change it to $a+n$. Feb 25 comment Eigenvalues of Symmetric Pseudo-Toeplitz Matrix I suppose you checked en.wikipedia.org/wiki/Tridiagonal_matrix#Determinant and noticed that due to this, you can write down the characteristic polynomial quickly. Apr 5 comment Dominated convergence theorem and fundamental lemma this looks like a meaningful question... Mar 26 comment Proving that $(e^x+1)^{1/3}$ has no elementary antiderivative well, consider my answer being done by computer, not me :-) Mar 22 comment Determinant of a Vandermonde matrix of roots of monic polynomial with integer coefficients the square of the Vandermonde is a symmetric function, and thus Per's argument applies. Mar 18 comment Nauty software package and weighted graphs There is no such command in dreadnaut. You will have to supply it the already prepared non-weighted graph. Mar 18 comment Nauty software package and weighted graphs Well, how you represent weights is an entirely different question. In the setting of computing automorphisms and isomorphisms all what matters is that different weights are represented by different integer numbers (or colours). Jan 21 comment How unitarize an irreducible representation of a finite group? In fact you don't need to compute eigenvalues and eigenvectors. Although you will still need to compute square roots of real cyclotomics at the end, as I mentioned in GAP forum. Sep 29 comment What is the second least non prime order of a simple group? PSL(3,2), not PSL(7,2) Sep 28 comment divisibility of number of solutions of $x_1+\cdots+x_k=n$ I'm not 100% sure, but it seems that if $\gcd(n,k)=1$ then all the $k$ cyclic $k$-shifts of a solution are different. This means that the number of solutions is divisible by $k$. Dec 4 comment Complexity of multiplying Cauchy matrix by a vector I've edited the question. Hopefully someone reviews the changes. Nov 29 comment Complexity of multiplying Cauchy matrix by a vector this is the problem of multiplying a vector by a matrix, not solving linear equations... Sep 17 comment a question about odd cycle isn't a proof for $k=1$ trivial? Take 2 vertices $u_0,u_2$ at distance 2 (say, $u_0u_1u_2$ is a path connecting them). Then there should be a length $2k+1=3$ path $u_0v_1v_2u_2$ between them, too. Now take all the vertices $u_i$ and $v_j$ - they form a 5-path, right?