123,621 reputation
8117239
bio website von-eitzen.de/math/tntrep.xml
location Bonn, Germany
age 48
visits member for 2 years, 3 months
seen yesterday

I did study math and had a knack for it, but I am sooo out of that business now ...


2d
comment Have any definitions in mathematics been redefined
And what they called prime back then would be called irreducible today :)
2d
comment Constructing an entire function
@Ian This should be an answer
2d
answered How to come up with bijections?
2d
answered How does the function work?
2d
revised Solve $f\left(\frac{x-3}{x+1}\right)+f\left(\frac{x+3}{x+1}\right)=x$ $\forall x\neq -1$
added 6 characters in body
2d
reviewed Close Set of all linear combinations of the vectors is a subspace
2d
reviewed Leave Open Is the hesse normal not a popular description for a line,plane?
2d
reviewed Close Number pattern prediction algorithm
2d
reviewed Close Proving $L_{\mathbb{X}}i_{\mathbb{Y}}=i_{[\mathbb{X},\mathbb{Y}]}+i_{\mathbb{Y}}L_{\mathbb{X}}$
2d
reviewed Close 8th positive odd integer that is an ODD Catalan number?
2d
answered Why schemes are $(X,\mathcal O_X)$ rather than $(\mathcal O_X,X)$ or $\{X,\mathcal O_X\}$
2d
comment Proofs involving positive real numbers
@TareqAhmed I do not assume that $\mathbf a$ and $\mathbf b$ are identically distributed, only that the $b_i$ (or the $a_i$) are i.i.d. - Without this, the estimate may be terribly off: If $N=2$ and $a_1,b_1$ are uniform random $\in\{100,101\}$ and $a_2,b_2$ are uniform random in $\{1,2\}$, then $\frac1N\sum \mathbf a\sum\mathbf b\le 5304.5$ whereas $\langle\mathbf a,\mathbf b\rangle \ge 10001$.
2d
revised How to define a transition matrix mathematically?
added 290 characters in body
2d
answered How to define a transition matrix mathematically?
2d
comment How to prove this number is not rational?
What do you know about $\alpha$? There certainly exist $\alpha\in(0,1)$that make $x$ rational. (And why does your title talk about integers, when the question is about rationals?)
Dec
16
comment Is Cantor's diagonal argument dependent on the base used?
The problem with base $2$ is that you might create an anti-diagonal number $0.01111111111111\ldots$ that differs from all binary sequences and yet represents the number $0.10000\ldots$ that possibly is ion the list.
Dec
16
answered How do I prove this function doesn't exist?
Dec
16
comment How do I prove this function doesn't exist?
Where $S$ is any set?
Dec
16
revised Why is $\varphi$ called “the most irrational number”?
added 3 characters in body
Dec
16
comment Proofs involving positive real numbers
@TareqAhmed Yeah, I should use the notation I introduce somewhere ;)