6.51.1 Top new questions this week

6.51.1.1 Strange symbol seen in an article

https://tex.stackexchange.com/landing/r/digest?cta=question&id=561461

I am reading H. Sati and U. Schreiber's article "Proper Orbifold Cohomology" -- seehttps://arxiv.org/pdf/2008.01101. On page 2, there is a formula almost at the bottom of the page, with a ... 
[fonts] [symbols]
 

asked by Mikael https://tex.stackexchange.com/landing/r/digest?cta=user&id=223948 15 votes

answered by Harald Hanche-Olsen https://tex.stackexchange.com/landing/r/digest?cta=user&id=1424 25 votes

6.51.1.2 Who designed the mathematical blackboard bold letters of AMS, and when?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=561380

Recently I have been investigating some history of the mathbb(mathematical blackboard bold) letters of AMS, which can be called by invoking amsfonts or amssymb package. 
By the content on page 35 of ... 
[tex-history]
 

asked by M. Logic https://tex.stackexchange.com/landing/r/digest?cta=user&id=140814 14 votes

answered by barbara beeton https://tex.stackexchange.com/landing/r/digest?cta=user&id=579 13 votes

6.51.1.3 Combinatorial notation (\choose) not working with \frac

https://tex.stackexchange.com/landing/r/digest?cta=question&id=561642

I want to display the following 
$p_N= \frac{{200 \choose 11}{ 200 \choose {N-189}}}{200 \choose N}$ 
However, texmaker gives me this error: 
Does anybody know why is that? I have tried replacing the ... 
[equations] [amsmath] [fractions]
 

asked by Kanye West https://tex.stackexchange.com/landing/r/digest?cta=user&id=208378 9 votes

answered by egreg https://tex.stackexchange.com/landing/r/digest?cta=user&id=4427 18 votes

6.51.1.4 Problem with \mathbb and superscript number

https://tex.stackexchange.com/landing/r/digest?cta=question&id=561866

I wrote \mathbb{R^2} in the editor, however what gets printed in the pdf is the turnstile symbol in the exponent instead of 2. 
I have the following packages: 
\documentclass[10pt,a4paper]{article} 
\... 
[math-mode] [amsmath] [mathbb]
 

asked by Asinus https://tex.stackexchange.com/landing/r/digest?cta=user&id=53895 5 votes

answered by egreg https://tex.stackexchange.com/landing/r/digest?cta=user&id=4427 8 votes

6.51.1.5 Itemize using multicol package

https://tex.stackexchange.com/landing/r/digest?cta=question&id=561772

I am doing a problem set for students and I would like to itemise horizontally a list of them. However when I try to do that one of the items appears a little bit above the rest of items and the ... 
[math-mode] [itemize] [multicol]
 

asked by RubA~(c)n PA~(c)rez Sanz https://tex.stackexchange.com/landing/r/digest?cta=user&id=195186 5 votes

answered by Mico https://tex.stackexchange.com/landing/r/digest?cta=user&id=5001 5 votes

6.51.1.6 Adjusting the vertical position of the limits of a sum

https://tex.stackexchange.com/landing/r/digest?cta=question&id=562101

Is there a way to vertically adjust the lower limits of the two sums below, such that 'p' and 'q' are vertically aligned? 
\sum_{p=1}^{\mathcal{M}}\sum_{q\in\mathfrak{N}_p^+} 
EDIT: As per egreg's ... 
[math-mode] [vertical-alignment] [math-operators] [subscripts] [mathtools]
 

asked by niran90 https://tex.stackexchange.com/landing/r/digest?cta=user&id=218434 4 votes

answered by egreg https://tex.stackexchange.com/landing/r/digest?cta=user&id=4427 4 votes

6.51.1.7 Why is the geometry package messing my margins up?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=562072

I want to write a document making use of as much of the page as I can. The code I am using is this (disclaimer: I took the sample text from here): 
\documentclass[12pt, oneside, a4paper]{memoir} 
\... 
[margins] [geometry]
 

asked by Iovita KemA~(c)ny https://tex.stackexchange.com/landing/r/digest?cta=user&id=222862 4 votes