User Douglas S. Stones - Mathematics Stack Exchange

Douglas S. Stones

Member for 13 years, 9 months
Last seen more than 10 years ago

sites.google.com/site/rknmodn
Halifax, Canada

417 Answers

Score Activity Newest

6 votes

Graph with multiple Eulerian trails/circuits.

answered Jan 4, 2013 at 9:53

6 votes

Prove that a graph is Hamiltonian

answered Nov 1, 2012 at 13:36

6 votes

Accepted

Coloring Graph Problem

answered Nov 1, 2012 at 11:07

6 votes

How to construct a k-regular graph?

answered Nov 5, 2012 at 6:13

5 votes

The number of non-isomorphic spanning trees in K4

answered May 19, 2013 at 17:13

5 votes

How do you find a basis for the set of all $3 \times 3$ matrices whose rows and columns add up to zero?

answered Oct 17, 2012 at 8:23

5 votes

Accepted

Is there a largest "nested" prime number?

answered Sep 26, 2012 at 4:14

5 votes

Are infinite cycle graphs just "straight lines"?

answered Jan 5, 2013 at 9:13

5 votes

$5n+1$, $3n-1$ problem, smallest repeating cycle and Collatz conjecture

answered Dec 26, 2012 at 7:21

5 votes

Solving $x^3=y$ in a group whose order is not divisible by $3$.

answered Dec 31, 2012 at 3:11

5 votes

Accepted

How to come up with a recurrence relation?

answered Nov 5, 2012 at 6:29

5 votes

All connected planar graph with girth at least 6 are 3-colourable

answered Jan 5, 2013 at 10:54

5 votes

Can you encode if-then-else in arithmetic

answered Jan 4, 2011 at 21:36

5 votes

Accepted

Directed graph with all indegree = outdegree = 1

answered Dec 15, 2010 at 9:28

5 votes

Accepted

How to find the number of $k$-permutations of $n$ objects with $x$ types, and $r_1, r_2, r_3, \cdots , r_x$ = the number of each type of object?

answered Aug 15, 2010 at 6:14

5 votes

Checking whether a graph is planar

answered Oct 10, 2012 at 7:11

5 votes

The set $\{g^2 | g \in G\}$ in a group $G$

answered May 1, 2012 at 11:07

5 votes

Accepted

Sum of powers and prime numbers

answered Sep 14, 2012 at 4:45

5 votes

Accepted

Partial Latin squares of even order

answered Jul 12, 2012 at 5:21

5 votes

Latin squares that don't come from group tables?

answered Jul 14, 2012 at 3:45

5 votes

Graph theory and Burnside's lemma

answered Oct 17, 2012 at 8:14

5 votes

Re-write $1 \cdot x$ to $x$.

answered Sep 21, 2013 at 21:34

5 votes

Calculate or approximate $\sum\limits_{k=801}^{849}{ \binom {2400} {k}} $

answered Apr 15, 2013 at 19:11

5 votes

Accepted

The graphs in which radius is equal to diameter

answered Apr 18, 2013 at 12:08

5 votes

Accepted

Why taking a bomb with you to the airplane won't improve your chances of survival

answered Apr 9, 2013 at 16:06

5 votes

Friendship paradox demonstration

answered Apr 9, 2013 at 23:16

5 votes

Accepted

Gallery of unlabelled trees with n vertices

answered May 31, 2013 at 12:59

5 votes

Accepted

What is the algorithm to permute a set of elements in to a fixed length?

answered Apr 19, 2013 at 15:16

5 votes

Probability of random integer's digits summing to 12

answered Apr 25, 2013 at 18:24

5 votes

Accepted

Applications of design theory

answered May 13, 2013 at 14:42

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