11,810 reputation
21650
bio website
location Monkey Island, OK
age
visits member for 2 years, 2 months
seen 12 hours ago

Hello, I am a freshman at The National Autonomous University of Mexico (UNAM).

My interests are contest problems,elementary number theory, combinatorics, graph theory, linear algebra, group theory, abstract algebra and I have been meaning to learn category theory and matroids.


Aug
5
comment Polygons with equal area and perimeter but different number of sides?
are you sure that works for any arbitrary n,n and an y arbitrary n-gon?
Aug
2
comment Number of ways to select numbers, each 1 from different lists without repetition
It is hard, you can look up the proof that the exact cover problem is $NP$ complete, this implies it is also hard to find the exact number of solutions
Aug
1
accepted If a group contains a subgroup with the order of each of its divisors, is it abelian?
Aug
1
comment If a group contains a subgroup with the order of each of its divisors, is it abelian?
well, I guess the fact that it exists is enough, why is it unique?
Aug
1
comment If a group contains a subgroup with the order of each of its divisors, is it abelian?
Oh, thanks for the short answer, I am having touble with why there is a unique nonabelian group of order $pq$
Aug
1
asked If a group contains a subgroup with the order of each of its divisors, is it abelian?
Aug
1
answered Number of ways to select numbers, each 1 from different lists without repetition
Aug
1
comment Number of ways to select numbers, each 1 from different lists without repetition
This is going to be hard.
Aug
1
comment Find a group G such that Z(G/Z(G)) is nontrivial when Z(G) is the center of G.
meta.math.stackexchange.com/questions/5020/…
Jul
31
answered Can two cycles be the inverse of each other if they are disjoint?
Jul
31
comment Neither $\log x$ nor $\exp(x)$ are rational functions
I think it's a good excercise to try to see why. I can give an explanation if it is required.
Jul
30
answered Neither $\log x$ nor $\exp(x)$ are rational functions
Jul
30
comment How many graphs can have the same line graph?
Excelent, thank you very much. this is exactly what I was looking for.
Jul
30
accepted How many graphs can have the same line graph?
Jul
30
asked How many graphs can have the same line graph?
Jul
28
answered Choosing $2$ groups of $5$ members and $1$ group of $2$ members from $15$ person
Jul
28
comment Why is it that if I count years from 2011 to 2014 as intervals I get 3 years, but if I count each year separately I get 4 years?
Oh, I was just saying the flaw in the reasoning that he had worked in 2011,2012,2013,2014 because he hadn't in fact worked all of 2014.
Jul
27
answered Maximum possible parts of a cake if cut n times
Jul
27
answered Why is it that if I count years from 2011 to 2014 as intervals I get 3 years, but if I count each year separately I get 4 years?
Jul
25
awarded  Nice Answer