current community
chat
MathOverflow
MathOverflow Meta
your communities
Sign up
or
log in
to customize your list.
more stack exchange communities
company blog
Stack Exchange
Inbox
Reputation and Badges
sign up
log in
tour
help
Tour
Start here for a quick overview of the site
Help Center
Detailed answers to any questions you might have
Meta
Discuss the workings and policies of this site
About Us
Learn more about Stack Overflow the company
Business
Learn more about hiring developers or posting ads with us
MathOverflow
Questions
Tags
Users
Badges
Unanswered
Ask Question
Profile
Activity
Gottfried Helms
Meta User
Network Profile
Reputation
2,522
2.5k
1.8k
1k
2013
2014
2015
2016
Top tag
nt.number-theory
Next privilege
3,000 Rep.
Cast close & reopen votes
Badges
1
7
20
Newest
Necromancer
Next badge
0/1
Custodian
Impact
~
122k
people reached
12 posts edited
9 helpful flags
247 votes cast
summary
answers
questions
tags
badges
favorites
bounties
reputation
all actions
77
Answers
newest
activity
votes
10
Is $ \sum\limits_{n=0}^\infty x^n / \sqrt{n!} $ positive?
Jan 5 '12 at 22:29
10
Eigenvalues of infinite matrices
Oct 15 '12 at 0:48
9
German mathematical terms like “Nullstellensatz”
Apr 19 '11 at 9:05
9
The functional equation $f(f(x))=x+f(x)^2$
Dec 18 '10 at 11:07
7
How to prove that this equation has only one solution?
Jun 25 '15 at 12:08
7
A question on Collatz's conjecture:proportion of “low flying” orbits
Feb 21 '15 at 14:25
6
Inverse of the Riemann zeta function
Aug 10 '11 at 11:53
5
f(f(x))=exp(x)-1 and other functions “just in the middle” between linear and exponential
Nov 3 '10 at 11:07
5
Does the formal power series solution to $f(f(x))= \sin( x) $ converge?
Nov 11 '10 at 7:04
5
Implication for m-cycles in Collatz-type problems.
Oct 15 '11 at 19:01
5
The functional equation $f(f(x))=x+f(x)^2$
Dec 19 '10 at 17:06
4
Does the formal power series solution to $f(f(x))= \sin( x) $ converge?
Nov 11 '10 at 23:49
4
Does the formal power series solution to $f(f(x))= \sin( x) $ converge?
Mar 11 at 22:33
4
Inequality of arithmetic, geometric and harmonic means
Sep 11 '14 at 3:26
4
Solving $x^k+(x+1)^k+(x+2)^k+\cdots+(x+k-1)^k=(x+k)^k$ for $k\in\mathbb N$
Oct 6 '13 at 22:33
4
Is $ \sum\limits_{n=0}^\infty x^n / \sqrt{n!} $ positive?
Jan 6 '12 at 5:15
4
Math for a cake
Dec 29 '12 at 14:05
4
Larger cycle than 4, 2, 1 in Collatz iteration?
Jun 24 '11 at 19:33
4
Longest coinciding pair of integer sequences known
Jan 15 '11 at 5:03
4
Nontrivial question about Fibonacci numbers?
Nov 19 '10 at 22:03
4
The non-convergence of f(f(x))=exp(x)-1 and labeled rooted trees
Nov 4 '10 at 7:50
3
3n+1 problem and cycles
Mar 16 '15 at 11:36
3
On an example of an eventually oscillating function
Mar 2 '15 at 18:16
3
Is there a known solution to $f(x) = (1-x)f(x^2)$?
May 16 '14 at 18:52
3
Is there a known solution to $f(x) = (1-x)f(x^2)$?
Apr 1 '14 at 7:32
3
Infinite matrix leading eigenvector problem
Feb 16 '14 at 12:58
3
Alternative to Choleski Decomposition for Correlation Matrix
Aug 13 '13 at 18:30
3
A curious sequence of rationals: finite or infinite?
May 25 '13 at 5:44
3
How to interpret this class of numbers?
Jul 28 '12 at 9:57
3
Negative values of Riemann zeta function on the critical line.
Aug 18 '11 at 1:14
MathOverflow works best with JavaScript enabled