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zbh2047
  • Member for 6 years, 2 months
  • Last seen more than 1 year ago
  • Beijing, China
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17 Questions

Score Activity Newest Views
10 votes
1 answer
10k views

Expectation of the norm of a random vector

7 votes
3 answers
2k views

Prove that a sub-Gaussian random vector over a finite set $S \subset\mathbb R^n$ implies that $|S|$ is exponentially large

7 votes
1 answer
348 views

A Bitwise Xor Problem

5 votes
1 answer
213 views

Consider a sequence $a_i=p \mod a_{i-1}$, where $p$ is a prime number, how to estimate the smallest $i$ where $a_i=1$? [duplicate]

4 votes
2 answers
613 views

The maximal size of intersection of two sets

3 votes
2 answers
2k views

The norm of isotropic sub-Gaussian random vector may not be sub-Gaussian

2 votes
1 answer
548 views

Lipschitz continuity of an implicit function

2 votes
2 answers
113 views

A linear equation problem related to projection

1 vote
0 answers
81 views

Algorithm for efficiently calculating $(A+\sum_{i=1}^n B_i)^{-1}$ where $A^{-1}\in\mathbb S^n_+$ is known and $B_i$ are sparse matrices

1 vote
0 answers
140 views

Lipschitz continuity of an implicit function generated by a monotonic and Lipschitz multivariate function

1 vote
1 answer
201 views

Estimate $\frac 1 {a+b} + \frac 1 {(a+b)(a+2b)} + \cdots + \frac 1 {(a+b)\cdots(a+kb)} + \cdots$ [closed]

1 vote
0 answers
111 views

The upper bound of the number of points of a convex hull formed by external co-tangents of circles

1 vote
1 answer
567 views

The minimum possible degree of a graph of $n$ vertices, in which all pairs of nodes have a distance no more than $d$

0 votes
1 answer
120 views

How many integers $x$ satisfy that $x*p(x) \leq n$, where $p(x)$ means the largest prime factor of $x$?

0 votes
1 answer
43 views

For an one-order Linear Recurrence of a vector sequence, does the corresponding item follow a Linear Recurrence? [closed]

0 votes
0 answers
102 views

Existence of distance-preserving mappings for general norm in vector space

0 votes
0 answers
284 views

Convergence of heavy-ball method for non-convex optimization