# All Questions

29 views

### Question about LP Programming model [closed]

I have a aggregate production planning problem. As the company want to have a stable output, the quantities produced per month should (x) not fluctuate to heavily from a specified amount, say g. So ...
33 views

### Random selection probability [closed]

A test was given to a group of students. The grades and gender are summarized below: ...
291 views

### Distribution of the sequence $\bigl (\frac{\phi(n)}{n}\bigr )_{n=1}^{\infty}$ in $[0,1]$

Maybe this is a well-know problem. What do we know about distribution of the sequence $\bigl (\frac{\phi(n)}{n}\bigr )_{n=1}^{\infty}$ in $[0,1]$? (Where $\phi$ is the Euler's totient function). In ...
111 views

### university press specialized in math books [closed]

I am thinking of writing a book for graduate students, on graph theory. Apart from AMS book, does someone of you could suggest a university press that acccept submission on these arguments. I ...
68 views

### Does an ISI journal need to have Impact Factor? [closed]

There are a bunch of journals in Springer and Elsevier without having impact factors. Are they considered ISI journals?
151 views

161 views

### Examples of quotients by infinitesimal group schemes

I'm looking for examples of explicit actions of the infinitesimal group schemes $\alpha_{p^n}$ on schemes (maybe as simple as the affine plane) in characteristic $p$ or mixed characteristic, and their ...
67 views

### Non-compact and maximal non-$T_2$ [migrated]

Is there a space $(X,\tau)$ that is not compact, not $T_2$, but for every topology $\tau'\supseteq \tau$ with $\tau'\neq\tau$ the space $(X,\tau')$ is $T_2$?
158 views

### Automorphisms of complete local rings

Let $k$ be a field and $(A,m)$ be the completion of the local ring of a smooth point of a $k$-variety. Let $x_1,x_2\in m\backslash m^2$ be regular elements. I am interested in knowing if one can find ...
118 views
+50

### What is the complexity of determining Ramsey Number?

In the notation of Garey and Johnson [1], two problems related to Ramsey Problem were defined: $\textbf{ARROWING}$ Instance: (Finite) graphs $F$, $G$ and $H$. Question: Does $F\rightarrow (G, H)$? ...