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I'm currently a graduate student at University of Washington. I'm interested in combinatorics.


Jan
21
comment What is the number $p(n)$ of partitions of an abundant number $n$ into distinct, proper divisors of $n$?
@WillJagy Ah, I didn't notice that they needed to be distinct.
Jan
21
comment What is the number $p(n)$ of partitions of an abundant number $n$ into distinct, proper divisors of $n$?
See oeis.org/A018818
Jan
19
comment How many analytic functions are there on a given set
The zero function vanishes everywhere, not just on $S$. Is there another function $f(z)$ so that $f(z) = 0$ when $z \in S$ and $f(z) \neq 0$ when $z \notin S$?
Jan
19
comment How many analytic functions are there on a given set
But $f \equiv 0$ does not vanish only on $S$.
Jan
16
comment Is the Center of Math Wrong?
@symplectomorphic: The goal is pretty clear from the context here. I don't think it's really necessary to clarify this every time, although it might help.
Jan
16
comment Is the Center of Math Wrong?
@GFauxPas Well, I will agree with you that the question isn't mathematical in the strictest sense of that word. But I still think that answering "it could be anything!" without admitting that some answers are better than others is not helpful.
Jan
16
comment Is the Center of Math Wrong?
I must disagree that these sort of problems are "stupid". They are ill-defined to some extent, perhaps. But there is often a solution that is simpler than others. If you think that the sequence 1,2,3,4,5,... should be followed by 78, -39, 23 then you are being obstinate. Occam's razor applies here; it is clear that the spirit of the question is to find a simple pattern.
Jan
13
comment Name for a nowhere constant function?
I don't think there's a name for this. But what do you mean by an interval $I \subseteq \mathbb{R}^n$?
Jan
8
comment Confusion on the proof that there are “arbitrarily large gaps between successive primes”
Yes. For a fixed $N$, you're trying to find a gap of at least $N$ consecutive numbers, all of which are prime. To do this, you need to cleverly choose a first number $a$, and then prove that $a, a+1, \ldots, a + N-1$ are all composite. Our clever choice is $a = (N-1)! + 2$. This choice doesn't arise naturally from the problem, like in many beginning number theory proofs - it's a something of a trick.
Jan
8
comment How can I prove whether a $9\times 9$ square can be filled with L-shaped pieces in a completely “regular” way?
Your proof seems fine to me.
Jan
7
awarded  Pundit
Jan
7
comment Is arrow notation for vectors “not mathematically mature”?
Yes, it's pretty rare to see the arrows in published papers. Mostly they just appear in undergraduate textbooks.
Jan
4
answered Besides proving new theorems, how can a person contribute to mathematics?
Dec
18
comment If R is an integral domain disprove the RxR is an integral domain?
No, it's not true that $Z_5 \times Z_5 \cong Z_{25}$.
Dec
9
comment Locus of centroid
@MvG: Ah, I misread the problem. I did not see the words "tangent plane".
Dec
9
comment Locus of centroid
This is a two-part problem. First find the intersection with the coordinate axes by setting $x,y = 0$; then $x,z = 0$, then $y,z = 0$. Then use the formula for the centroid of a triangle.
Dec
8
awarded  Caucus
Dec
2
comment Is a proposition about something which doesn't exist true or false?
Ah, I see what you mean. Thanks!
Dec
2
comment Is a proposition about something which doesn't exist true or false?
I'm not sure if I understand why the first statement would be true. I thought that $\{x: x \notin x\}$ would not even be grammatically correct in this context unless you change it to $\{x \in U: x \notin x\}$ for some fixed set $U$. A sentence like $(\forall z)[ (z = \{ x : \in :x\}\}\}\}) \to ( |z| = 1)]$ would not have a truth value, would it?
Nov
25
comment Will it become impossible to learn math?
+1. Perfect answer!