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location Moscow
age 37
visits member for 4 years
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2d
awarded  Enlightened
2d
awarded  Nice Answer
2d
awarded  Excavator
2d
revised Finite interpolation by a nondecreasing polynomial
The last formula corrected in non-mathematical part.
2d
comment Zero divisors with support of size 3 in group algebras of finite groups
One may simplify the opposite direction argument by observing that $\mathbb F[G]/I(G)\cong \mathbb F$ via the epimorphism $\sum_{g\in G}\alpha_gg\mapsto \sum_{g\in G}\alpha_g$. This applies to all groups, not only finite ones.
Aug
31
revised Polynomial interpolation of binary word signal
Clarified that both papers work with the use of Chebyshev polynomial trick.
Aug
31
answered Polynomial interpolation of binary word signal
Aug
31
comment Zero divisors with support of size 3 in group algebras of finite groups
If such elements exist for some group, they also exist for every overgroup. So it is more reasonable to make the least prime divisor of $|G|$ large.
Aug
30
comment Number of linearly bisected subsets in finite vector space $F_2^n$
Do you know any non-bisectable subset of even size?
Aug
30
answered Zero divisors with support of size 3 in group algebras of finite groups
Aug
30
comment Zero divisors with support of size 3 in group algebras of finite groups
One of the definitions of a group algebra regards its elements as functions from $G$ to $\mathbb F$.
Aug
29
awarded  Revival
Aug
29
revised Fixed point of fatness
Remark has been rewritten
Aug
29
comment Fixed point of fatness
Yes, I have already realizd that, sorry.
Aug
29
answered Fixed point of fatness
Aug
28
comment Existence of finite set of points in the revolving circles
Let us continue this discussion in chat.
Aug
28
comment What is the maximum size of a set system where the intersection of any two incomparable members is not in the set?
Josh, if you try to construct an optimal system for $n=8$ in this manner (taking some complete layers of the cube), you will come up with the system of the 8-set, all 6-sets, and all 3-sets (all other combinations lose to this one). BUT THEN you may also add ONE 7-set without troubles! So an optimal example becomes more complicated, no matter whether it is the resulting one or not.
Aug
27
comment Existence of finite set of points in the revolving circles
Here you are; sorry again for that mess in the initial remark.
Aug
27
revised Existence of finite set of points in the revolving circles
Remark is changed, a picture is added.
Aug
27
comment Existence of finite set of points in the revolving circles
On the other hand, I was also a bit wrong in describing the example, sorry. I'll correct it and make a picture quite soon.