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location Monkey Island, OK
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visits member for 2 years, 2 months
seen 18 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.


Jun
16
comment Even Odd counting
I'm sorry, I'm not a programmer, I do not understand any of this.
Jun
16
comment Conditional probability with pigs and cherries
Well, we have no information about what the cherries selected by the pig where, so effectively it is the same as just picking a random cherry,
Jun
16
answered Conditional probability with pigs and cherries
Jun
16
answered Proving a division propositon?
Jun
16
answered Is the average of a set of numbers minus a constant the same as each number minus the constant averaged?
Jun
16
revised Is the average of a set of numbers minus a constant the same as each number minus the constant averaged?
added 24 characters in body
Jun
16
answered Simple Mathematics equation
Jun
16
comment finding the combination of sum of M numbers out of N
Oh, this looks a lot harder, I'll think about it.
Jun
16
comment finding the combination of sum of M numbers out of N
Oh, you can't repeat numbers and the order does not matter? In that case the approach in your question does not work either.
Jun
16
comment finding the combination of sum of M numbers out of N
yup, this is exactly the problem I am answering :) Here is a similar question math.stackexchange.com/questions/620640/…
Jun
16
answered Is a function $f:\mathbb{Z}^2\rightarrow\mathbb{Z}$ injective?
Jun
16
revised Prove that $\sin A - \sin B + \sin C = 4\sin A/2 \cos B/2 \sin C/2$
added 13 characters in body; edited title
Jun
16
answered Help complete proof ('or' statement in conclusion): $a^2 \ge 7a \Rightarrow a\le0 \text { or } a\ge7$
Jun
16
comment finding the combination of sum of M numbers out of N
This is just a simpler way to calculate the coefficient of $x^N$, it does this by calculating the coefficients of $(1-x^k)^m$ and the coefficients of $(1-x)^{-m}$ and cross multiplying those which give the desirable exponent $x^n$.
Jun
16
answered finding the combination of sum of M numbers out of N
Jun
16
answered For every integer, some multiple of it is of the form $99 \ldots 900 \ldots 00$
Jun
16
comment For every integer, some multiple of it is of the form $99 \ldots 900 \ldots 00$
Neat problem, But you didn't really do anything.You didn't express the numerator or prove $a$ is an integer.
Jun
16
answered What does this combination notation mean?
Jun
16
answered Definitions of noncooperative and cooperative games.
Jun
16
answered How to determine the round of a game given it's state number?