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1 vote
0 answers
7 views

Projected gradient descent 投影梯度下降的收敛速度

4 votes
2 answers
2k views

Prob. 3, Sec. 22, in Munkres' TOPOLOGY, 2nd edition: How is this map a quotient map that is neither open nor closed?

4 votes
1 answer
223 views

Absolute value notation is ambiguous

2 votes
1 answer
45 views

If $0<q<2000$, then at most $10$ consecutive terms of the arithmetic progression $a,a+q,a+2q\dots$ can be primes

0 votes
1 answer
28 views

Let $S\subseteq \{1,2,...,3n\}$ be a set of cardinality $2n+1$. Prove there exist $x,y \in S$ such that $x|y$.

0 votes
1 answer
39 views

How to factorize the above expression?

0 votes
2 answers
30 views

Prove that the functor $P : \text{Set}^\text{op} → \text{Set}$ , $F(f)=f^{-1}:P(Y)\rightarrow P(X)$ for $f: X \rightarrow Y$ is representable

1 vote
0 answers
71 views
+50

When is $A \leq B$ with fixed probability $p> \frac{1}{2}$ a partial order?

1 vote
0 answers
19 views

Ambiguity in order of operations

1 vote
0 answers
7 views

Show that the map $(z,w) \mapsto (z^{am} w^{bn}, z^{cm} w^{dn})$ is a covering map.

0 votes
0 answers
4 views

Two families of random variables that are identically distributed then what about their $\limsup$

0 votes
0 answers
3 views

Does Gaussian Process solve specified distribution drift problem?

0 votes
0 answers
4 views

Necessary and sufficient condition for line of curvature to be parametric curve

0 votes
0 answers
4 views

Adding random noise to an ill-posed problem

1 vote
1 answer
1k views

Proving intersection of two regular languages is regular with Myhill Nerode

1 vote
1 answer
47 views

Condition on group\ring that satisfies solutions for 'linear equations'

5 votes
0 answers
142 views

Union of two disjoint congruent polygons is centrally symmetric. Must the polygons differ by a 180 degree rotation?

0 votes
0 answers
6 views

k - minimum spanning tree in a tree

0 votes
0 answers
8 views

How to compute the successor to a given floatting point number

0 votes
1 answer
37 views

Card Game Strategy

0 votes
0 answers
66 views

Find a constant if you know the limit

0 votes
0 answers
10 views

absolute difference on a relative scale

1 vote
0 answers
20 views

Understanding the bounded variable algorithm in the integer programming

13 votes
5 answers
1k views

Solve $\int \limits_{0}^{\infty} \frac{\cos(x)}{\cosh(x)} dx$ without complex integration.

0 votes
0 answers
13 views

functional calculus and laplacian

0 votes
0 answers
17 views

Find the Integrand from a definite integral

0 votes
1 answer
43 views

Can L'Hopital's rule be used when one of the limits is not defined?

0 votes
0 answers
28 views

What's the probability of a probability?

0 votes
0 answers
11 views

Find a linear system of equations whose solution set is the span of these vectors.

0 votes
0 answers
7 views

Express scheduling in propositional logic

0 votes
0 answers
32 views

Closed-form root of $1+\sin(x+\sin(x)/2)$?

2 votes
1 answer
24 views

Does there exist a topological non-metric unital algebra $V$ such that $\exp x$ is defined for all $x\in V$?

0 votes
0 answers
15 views

Question about transient states in markov chain

1 vote
0 answers
7 views

Stochastic differential equation with Bernoulli random process as a solution

1 vote
0 answers
18 views

Questions about details in Lebesgue Outer Measure Theorem proof for an interval I , $|I|_e=v(I) $

0 votes
0 answers
3 views

Simple linear programming problem with dual objective

0 votes
1 answer
26 views

What is wrong of my understanding for Proposition 11 of Book III (Euclid's Elements of Geometry)

0 votes
0 answers
11 views

Semisimplicity implies separability for a perfect field

3 votes
1 answer
1k views

Differentiable top-k function

0 votes
0 answers
5 views

Coordinates after point multiplication not in elliptic curve.

0 votes
1 answer
46 views

Calculate the $ \lim_{r \to 1} {r(\sqrt{n-2}) /(\sqrt{1-r^2})}$, for every $n \in \mathbb{N} $

-1 votes
0 answers
15 views

equality of solution sets of linear equations

1 vote
0 answers
47 views

How can I prove the transitivity part of the following lemma?

0 votes
1 answer
29 views

Finding the Number of Permutations of three Children by Gender

0 votes
1 answer
1k views

How to compute unit direction vector of a ray in 3D given its origin and angle with XZ and YZ planes?

1 vote
1 answer
36 views

Find the density of sum of uniform random variable bounded by a triangle

2 votes
1 answer
38 views

The form of the intersection of two von neumann algebras

0 votes
0 answers
27 views

Is the set of Riemannian metrics with Partially Hyperbolic geodesic flow path connected?

0 votes
0 answers
5 views

Convergence of Distribution for a Modified Sequence of IID Random Variables

-1 votes
0 answers
9 views

Uniqueness condition for reaction diffusion PDE

1 vote
0 answers
18 views

Lattices and noncommutative algebras in noncommutative geometry

0 votes
0 answers
14 views

What is "equationalized axiom" in Wolfram FindEquationalProof?

1 vote
0 answers
19 views

What is a commutative infinity-algebra?

3 votes
0 answers
53 views
+100

Positive unbounded self-adjoint operator relatively bounded by sum with another positive unbounded self-adjoint operator?

5 votes
1 answer
69 views

Solving $\int_0^1\frac{\log^4(1-x^2)}{1+x}dx$

0 votes
0 answers
11 views

Prove that the map from a set of certian sequences to its limit is a bijection

3 votes
1 answer
50 views

The inverse map of the Poincare duality map

4 votes
0 answers
65 views

Derive a closed-form expression for $\int\limits_0^\infty \frac{u \operatorname{J}_0(xu)}{\sqrt{1+u^2} \sqrt{1+\beta u^2}} \, \mathrm{d} u$

3 votes
1 answer
48 views

Empirical distribution learns w.r.t total variation distance

0 votes
0 answers
21 views

What does it mean that the distribution of a variable is well-defined?

1 vote
1 answer
96 views

A certain map involving Eilenberg-MacLane spaces is a well-defined homomorphism (towards a universal coefficient theorem)

1 vote
0 answers
10 views

Change-detection filter

0 votes
1 answer
234 views

Splitting $f(x)$ in $K_n$ Extension Field. What is the maximum degree of $K_n$

1 vote
0 answers
33 views

Show that $\mathbb{E}(\mathbf{1}_{\{X>t\}}|\mathcal{G})$ is $(\mathcal{B}(\mathbb{R})\otimes\mathcal{G},\mathcal{B}(\mathbb{R}))$-measurable.

0 votes
0 answers
17 views

A PDE Exercise on the Maximum Principle

-1 votes
0 answers
18 views

How to the system of equations $a+b+c=3,2a+2b-c=1,5a-4b-3c=-7$?

0 votes
0 answers
12 views

Why every component of a loopless matroid is flat?

0 votes
0 answers
9 views

Is it true that for every initial distribution of the chips you can get any possible distribution?

0 votes
0 answers
10 views

Prove that there exists a local basis $\mathcal{D}$ s.t. $D_{1}\supseteq \dots \supseteq D_{n}$

4 votes
1 answer
88 views

Sharp constant $C$ for $\|x+y\|_p \leq C\| tx + (1-t)y\|_p$.

0 votes
0 answers
14 views

Domain of spectral Laplacian

1 vote
0 answers
16 views

equivalence of Sobolev space in manifolds

0 votes
0 answers
56 views
+50

Domain of the Cramér rate function, Exercise 2.2.39 in Dembo-Zeitouni

0 votes
1 answer
23 views

Closed subspace cut off by the ideal sheaf coming from a locally closed immersion

3 votes
0 answers
90 views

Limit of an integral involving a general $f(x)$

0 votes
0 answers
16 views

When are coordinate rings separable?

0 votes
0 answers
23 views

Definition of a Markov process on the real numbers.

0 votes
0 answers
9 views

How do i make prediction intervals without normally distributed residuals?

1 vote
1 answer
49 views

Fourier Transform of $x \delta(x)$

-3 votes
2 answers
42 views

Why don't prime counting approximations work for Brocard's conjecture?

1 vote
1 answer
20 views

Henon map's sink fixed point and saddle fixed point.

0 votes
0 answers
15 views

Tangent space at a point of product of algebraic varieties

0 votes
0 answers
17 views

conditional multivariate normal distribution using pdf only

1 vote
1 answer
23 views

Local coefficients of vector fields are smooth

0 votes
1 answer
13 views

Sub-gaussian norm vs. variance proxy

1 vote
0 answers
6 views

Monodromy Properties of Heun Functions in the Singularity Parameter

0 votes
0 answers
7 views

Volterra integral transformation in two dimensional case

5 votes
0 answers
37 views

Constrained geometry on manifolds

2 votes
0 answers
11 views

Advantage of Exponentiated Gradient over Gradient Descent

1 vote
0 answers
16 views

Mordular functions and modular forms

7 votes
0 answers
55 views

Does there exist $( x_n)_{n\in\mathbb{N}}\subset \mathbb{R}$ such that $\sum_{k=1}^{\infty} x_{kn} =1$ for every $n\in\mathbb{N}?$

1 vote
0 answers
21 views

Ex $1.17(3)$ in Brezis Functional Analysis

3 votes
2 answers
118 views

How to prove the 2nd question of sequence and series

6 votes
0 answers
597 views
+50

Modules over ring of formal power series

1 vote
0 answers
51 views

Localized estimate for divergence free vector field

0 votes
1 answer
70 views

The proof of Crossbar Theorem

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