6,297 reputation
33661
bio website front.math.ucdavis.edu/author/…
location New York City
age 44
visits member for 5 years
seen Oct 16 at 16:02
Research: additive number theory; combinatorial number theory. Faculty at City University of New York, at the Staten Island and Graduate Center campuses.

Oct
21
awarded  Yearling
Oct
17
awarded  Good Question
Oct
16
comment Computer Algebra Errors
That's a great article!
Sep
30
awarded  Explainer
Sep
23
comment List of integers without any arithmetic progression of n terms
Uh, yep, $f(2)=3$. I did $f(3)$ on my fingers, too, so no promises...
Sep
23
comment List of integers without any arithmetic progression of n terms
$f(1)=1$, $f(2)=4$, $f(3)=4$. Do you have some more numbers to report?
Sep
23
awarded  Necromancer
Aug
28
comment What is your favorite “strange” function?
It is definitely discontinuous at rational points. At $p/q$ the difference between the limit from the left and from the right is $1/(2^q-1)$, which is definitely not 0. It is differentiable at irrational $x$, and moreover its derivative is 0 whenever it has one!
Jul
31
awarded  Enlightened
Jul
31
awarded  Nice Answer
Jul
17
comment Computer Algebra Errors
I just asked Mathematica 10 to "Integrate[ Abs[Exp[2Pi I x]+Exp[2Pi I y]], {x,0,1}, {y,0,1}]", and after some thought it returned the expression unevaluated.
Jul
2
awarded  Curious
Jun
14
comment Enumeration of a finite group
Are there any groups you can confirm have, or don't have, such enumerations?
Mar
27
awarded  Nice Answer
Mar
22
comment partial sums of fractional parts
Isn't $S(28,18,1/2) = 336/23$, considerably larger than your numerics suggest?
Mar
22
comment partial sums of fractional parts
Just to be clear, typically $S(p,q,\alpha)$ is negative, and can be arbitrarily negative, you just want to bound how positive it can become?
Jan
9
awarded  Notable Question
Dec
13
comment Expected symmetry in the diophantine approximations of an irrational number
Do you have a proof that there are no upper ones? I think defining $x$ through its continued fraction may be more tractable, say $x=[0;10,1,100,1,1000,1,\dots]$.
Nov
10
comment Most interesting mathematics mistake?
That's what I had in mind, sorry for the confusion. But in my defense, can't circles on the surface of a torus have 4 intersections? And $p$-adic circles have infinitely many?
Nov
2
awarded  Famous Question