9,862 reputation
22874
bio website math.ucla.edu/~pak
location Los Angeles, CA
age
visits member for 5 years, 1 month
seen 1 hour ago

Mar
20
revised generating set for symmetric group $S_n$
added 35 characters in body
Mar
19
answered generating set for symmetric group $S_n$
Mar
1
comment 3D models of the unfoldings of the hypercube?
You might like a movie on the 2D case: etudes.ru/ru/etudes/cubisme
Feb
22
awarded  Nice Question
Feb
21
revised Linear groups which don't contain products of free groups
rewording
Feb
20
asked Linear groups which don't contain products of free groups
Feb
16
awarded  Yearling
Feb
11
awarded  Good Answer
Feb
9
revised Word complexity of primes mod 4
update, added refs
Feb
9
awarded  Nice Question
Feb
8
asked Word complexity of primes mod 4
Oct
21
revised Pach's “Animals”: What if the genus is positive?
link fixed
Oct
4
comment (non-)existence of the aperiodic monotile
Not exactly. That paper talks only about tilings of the plane with parallel traslates. These are MUCH easier than general tilings.
Sep
30
awarded  Explainer
Aug
15
awarded  Good Answer
Aug
8
comment What exact number of domino tilings cannot be realizable?
Let's say you have two integers $m<n$. Can you always find a s.c. region $G$ and a domino $D \subset G$, s.t. $G$ has exactly $n$ tilings, but $G-D$ has only $m$?
Jul
13
answered What is known about tiling a rectangle in an irreducible way by smaller rectangles?
Jun
14
answered A Simple Bijective Proof Of Stanley's Hook-Content Formula for Hook Shapes
May
6
awarded  Nice Answer
Mar
5
awarded  Enlightened