12.4.1 Top new questions this week

12.4.1.1 Graph theory, Hamiltonian paths, and Spell Weaving

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=318498

The New York Times Sunday magazine has a puzzle, Spell Weaving, illustrated in the figure. 
 
The top two small figures illustrate the puzzle and a solution.  You are given an $n \times n$ grid of cells,... 
[graphs-and-networks] [puzzle]
 

asked by David G. Stork https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=9735 Score of 9

answered by cvgmt https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=72111 Score of 6

12.4.1.2 How do I draw one side mesh in the two side surface?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=318478

We know that we could use  FaceForm[Blue, Orange]  in  PlotStyle  to color the inside and outside differently. Now I want to remove ... 
[plotting] [graphics3d]
 

asked by herbertfederer https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=74235 Score of 7

answered by cvgmt https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=72111 Score of 13

12.4.1.3 How to change  a[p,q],b[r,s]  to  a,b ?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=318511

Start with  mat={a[p,q],b[r,s] . 
I want to change this to  {a,b} . 
I get part way there with ... 
[list-manipulation] [assignment]
 

asked by matrixbud https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=42752 Score of 6

answered by cvgmt https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=72111 Score of 8

12.4.1.4 Boundary forces in finite element solid mechanics

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=318513

Following on from this post and very helpful answers I am trying to make sub-models of parts of a complex structure so I can look at forces at connections. When you cut out a sub-model from a larger ... 
[differential-equations] [finite-element-method] [solidmechanics]
 

asked by Hugh https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=12558 Score of 5

12.4.1.5 Replace atom in large protein structure

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=318486

How can I reproduce Figure 1 on this page, which shows a complex protein with either a lead atom or a calcium atom in a specific location?  Here's how to get a protein: 
... 
[chemistry] [biomolecularplot3d]
 

asked by David G. Stork https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=9735 Score of 5

answered by MelaGo https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=63360 Score of 6

12.4.1.6 Epilog and Prolog losing opacity when exporting

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=318475

Consider the following example 
 Plot[x/2, {x, -2, 2}, 
Epilog -> { 
Opacity[.2], 
Table[ 
Line[{{x, -2}, {x, 2}}], 
{x, -2, 2, .5} 
] 
} 
] 
 
In ... 
[bugs] [export] [pdf-format] [opacity] [epilog]
 

asked by Kai https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=53487 Score of 5

answered by cvgmt https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=72111 Score of 3

12.4.1.7 Problem from Kolmogorov Student Olympiad in Probability Theory 2025

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=318501

I try to solve the following problem from Kolmogorov competition 2025 (see here 
for the original formulation (There is a typo in the formulation: it should be $1-xy$ instead of $1+xy$.)) 
 
Let a random ... 
[probability-or-statistics]
 

asked by user64494 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=7152 Score of 4

answered by ubpdqn https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=1997 Score of 7