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Max Alekseyev

Washington, DC, United States

http://home.gwu.edu/~maxal/

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Top Questions
65 votes

Iterations of $2^{n-1}+5$: the strong law of small numbers, or something bigger?

nt.number-theory prime-numbers computational-number-theo integer-sequences divisors-multiples asked Oct 9, 2016 at 3:54
mathoverflow.net

44 votes

Relaxed Collatz 3x+1 conjecture

nt.number-theory collatz-conjecture asked Sep 3, 2015 at 17:05
mathoverflow.net

25 votes

Removal of non-isomorphic edges results in the same graph

co.combinatorics graph-theory extremal-graph-theory counterexamples asked Jul 15, 2014 at 17:44
mathoverflow.net

11 votes

When adding a constant makes a multivariate polynomial reducible?

computational-number-theo polynomials nt.number-theory diophantine-equations asked Mar 3, 2013 at 5:23
mathoverflow.net

11 votes

Integer values of a rational function

diophantine-equations rational-functions computational-number-theo nt.number-theory asked Jul 1, 2010 at 16:15
mathoverflow.net

10 votes

When polynomial f(x^2) can be factored as g(x)·g(-x) ?

nt.number-theory real-analysis algorithms polynomials asked Feb 27, 2013 at 17:45
mathoverflow.net

10 votes

Explicit expression for recursive sums

co.combinatorics polynomials recurrences asked May 8 at 21:41
mathoverflow.net

10 votes

Maximum matching in a graph with no "shortcuts"

co.combinatorics graph-theory conjectures matching-theory directed-graphs asked Mar 7, 2017 at 16:20
mathoverflow.net

7 votes

A hypergeometric identity related to Bessel functions

co.combinatorics hypergeometric-functions combinatorial-identities bessel-functions asked Jun 27, 2019 at 21:20
mathoverflow.net

7 votes

Expression for the sum of square roots of zeros of a polynomial

polynomials symmetric-functions real-analysis asked Feb 27, 2013 at 1:56
mathoverflow.net

1 2

Top Answers
103
Special rational numbers that appear as answers to natural questions
mathoverflow.net

64
Special rational numbers that appear as answers to natural questions
mathoverflow.net

29
Harmonic sums and elementary number theory
mathoverflow.net

24
Simple recurrence that fails to be integer for the first time at the 44th term
mathoverflow.net

24
When do binomial coefficients sum to a power of 2?
mathoverflow.net

23
$3^n - 2^m = \pm 41$ is not possible. How to prove it?
mathoverflow.net

22
Are there infinitely many positive integer solutions to $(3+3k+l)^2=m\,(k\,l-k^3-1)$?
mathoverflow.net

21
Positive roots of a polynomial
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20
Dividing squares by sums
mathoverflow.net

18
2-adic valuation of a certain binomial sum
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18
Almost-converses to the AM-GM inequality
mathoverflow.net

18
Are there infinitely many natural numbers not covered by one of these 7 polynomials?
mathoverflow.net

17
what is the status of this problem? an equivalent formulation?
mathoverflow.net

17
When do binomial coefficients sum to a power of 2?
mathoverflow.net

16
In search of a combinatorial reasoning for a vanishing sum
mathoverflow.net

15
The GCD-matrix: generalizing a result of Smith?
mathoverflow.net

14
$2$-adic valuations: a tale of two $q$-series
mathoverflow.net

14
How to get a closed form for a possibly simple combinatorial sequence
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14
What is Lagrange Inversion good for?
mathoverflow.net

14
Examples of integer sequences coincidences
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14
Prove that these are polynomials
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14
Squares in the set $\{\sum_{j=1}^m j^2: m\in\mathbb{N}\}$
mathoverflow.net

13
Integers $b$ such that $n \nmid (b^n-1)$ for $n>1$
mathoverflow.net

13
When is the number of areas obtained by cutting a circle with $n$ chords a power of $2$?
mathoverflow.net

13
What recent discoveries have amateur mathematicians made?
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12
Combinatorial identity: $\sum_{i,j \ge 0} \binom{i+j}{i}^2 \binom{(a-i)+(b-j)}{a-i}^2=\frac{1}{2} \binom{(2a+1)+(2b+1)}{2a+1}$
mathoverflow.net

12
Do you recognize this sequence of polynomials?
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12
Looking for a combinatorial proof for a Catalan identity
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12
How small (in modulus) can a polynomial get?
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11
Сlosed formula for $(g\partial)^n$
mathoverflow.net

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