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Gottfried Helms
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77
Answers
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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
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