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bio website math.haifa.ac.il/~seva
location Israel
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21h
awarded  Necromancer
1d
awarded  additive-combinatorics
1d
awarded  nt.number-theory
1d
comment Ordering subsets of the cyclic group to give distinct partial sums
Hm-m-m... All the coefficients being even means that $P$ is the zero polynomial in ${\mathbb F}_2$, which is wrong?
1d
comment Ordering subsets of the cyclic group to give distinct partial sums
@David: Do you mean the coefficient of $x_1^5\ldots x_5^5$? Well, quite possible. What are the coefficients of $x_1^5\ldots x_6^5/x_i^5$ for $1\le i\le 5$?
1d
comment Ordering subsets of the cyclic group to give distinct partial sums
@David: No typo (which is pretty unusual for me). We need $a_i+\ldots+a_j$ to be distinct from $0$ only for $1<i<j\le k$.
1d
answered Ordering subsets of the cyclic group to give distinct partial sums
Apr
14
comment Ordering subsets of the cyclic group to give distinct partial sums
Is there a simple proof for the real case? That is, given a set of $k$ non-zero real numbers, can we order them so as to have all the partial sums $a_1+\dotsb+a_i\ (1\le i\le k)$ pairwise distinct?
Apr
13
awarded  Notable Question
Apr
8
awarded  Nice Answer
Apr
3
revised Element with unique representation in A+B
added 1947 characters in body
Apr
2
revised Element with unique representation in A+B
edited tags
Apr
2
answered Element with unique representation in A+B
Mar
18
revised On a problem about $GF(2)^n$
Grammar, notation, tags edited.
Mar
18
answered On a problem about $GF(2)^n$
Mar
8
accepted Cyclotomic integers with given modulus
Mar
7
awarded  Revival
Mar
6
answered Cyclotomic integers with given modulus
Feb
27
comment Optimal covering
It might be helpful to re-state your problem in the following spirit: find an (easily computable) function $f\colon\{0,1\}^k\to\{0,1\}^{k+l}$ such that ${\rm Im}\,f+B_r=\{0,1\}^{k+l}$, where $B_r$ is the origin-centered unit ball of radius $r$. The dependence of $l$ and $r$ on $k$ must be stated very explicitly.
Feb
26
answered Pollard's inequality modulo a composite number