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Interesting 15 Bountied Hot Week Month
1 vote
2 answers
812 views

Trouble understanding permutation problem

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Sachin Sampath H
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5 votes
3 answers
116 views

Proof that $(ab)^{-1} = b^{-1}a^{-1}$ in an inverse semigroup $S$.

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linkja
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3 votes
3 answers
437 views

Prove that $\sum\limits_{cyc}\sqrt{\frac{8ab+8ac+9bc}{(2b+c)(b+2c)}}\geq5$

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amWhy
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0 votes
0 answers
13 views

Hardness of learning signs of subset sums with negations

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Matthew Finlayson
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0 votes
1 answer
37 views

Relationship between $\text{Tor}_R(M)$ being an $R$-module and $R$ being an Integral Domain

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rschwieb
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14 votes
2 answers
311 views

If $a+b+c+d=1$ so $\sum\limits_{cyc}\sqrt{a+b+c^2}\geq3$

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Leucippus
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2 votes
1 answer
72 views

Unramified iff norm map is surjective?

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Enguerrand Moulinier
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0 votes
1 answer
873 views

Show that a subset of a set of linearly independent vectors is linearly independent

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CommunityBot
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2 votes
1 answer
83 views

Tamely ramified extensions with a non-discrete valuation

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David Goldberg
  • 474
0 votes
1 answer
69 views

Fundamental theorem of calculus for heaviside function

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Silas
  • 284
1 vote
3 answers
253 views
+300

Solve the equation $[x]+\frac{2025}{[x]}=\{x\}+\left[\frac{2025}{\{x\}}\right]$ in the set of real numbers

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mathlove
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2 votes
1 answer
63 views

Upper bounding the Gauss hypergeometric function outside the unit disk $z=4$

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Jack D'Aurizio
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2 votes
0 answers
33 views

Set subtractions and translation

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A rural reader
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0 answers
8 views

Number of ways to arrange r distinct objects into 2 identical circles, stirling number of first kind

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Udbhav Dikshit
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0 votes
0 answers
9 views

Transient cylindrical heat equation in 1D, boundary conditions and Bessel functions

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bacardi sitron
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0 votes
2 answers
64 views

Can a larger subset have lower variance? A comparison of minimum-variance subsets of sizes $3$ and $4$

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Greg Martin
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0 votes
0 answers
6 views

References for weighted eigenvalue problems

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Edilson Pereira
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1 vote
2 answers
157 views

Counting the number of sets of natural numbers generated from two coprime numbers

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Simon Goater
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1 vote
5 answers
1k views

Where can i find a proof that the allowable dropping times on the collatz conjecture are $\lfloor1 + n \cdot \log_2(3)\rfloor$

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user140242
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2 votes
2 answers
117 views

Expectation of Sum of Squares for Truncated Normal RVs

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Ziv
  • 1,372
2 votes
2 answers
324 views

A product of a quotient map with an identity

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R. H. Vellstra
  • 3,327
3 votes
4 answers
278 views

characterization of a simple closed curve in two dimensions

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John Hughes
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0 votes
0 answers
39 views

Is this quaternion-valued differential operator already known in mathematics, and what are its implications?

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nav
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0 votes
3 answers
68 views

What is variance in context of projection of a vector?

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Saeed
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0 votes
1 answer
873 views

Cartesian equations for the line tangent to two surface.

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1 vote
0 answers
12 views

Reference Request: Integral Representations and the Jordan-Zassenhaus Theorem

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StAKmod
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0 votes
0 answers
12 views

Lemma 9.2.1 in Finite von Neumann Algebras and Masas

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SihOASHoihd
  • 1,068
3 votes
2 answers
205 views

Is a Hausdorff subtopology of a second countable space second countable?

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Jakobian
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3 votes
2 answers
865 views

Well-definedness of uncomputable functions.

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Apoloniusz Tyszka
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4 votes
2 answers
379 views

Find all polynomials such that $f(x)$ divides $f(2x^3+x)$

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Kevin Chen
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5 votes
2 answers
55 views

Cyclic symmetrisation giving zero

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Martin R
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0 answers
15 views

What does it mean for an isomorphism to transform one scalar product into another? (Neukirch ANT, Proposition 5.1 P30)

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1 vote
3 answers
89 views

$f(x)$ is continuous at $a$, and $g(x)$ is defined at $a$ but not continuous at $a$. Prove that $f(a)=0$ if $f(x)g(x)$ is continuous at $a$.

Xander Henderson's user avatar
Xander Henderson♦
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1 vote
2 answers
99 views

Show that $I^{2}/ {\sim} \cong S^{1} \times I$ without using compactness

Paul Frost's user avatar
Paul Frost
  • 88.9k
2 votes
0 answers
15 views

Convergence of fixed-point iteration $x = \frac{1 + Px}{2 + Px + Nx}$

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user3701010
  • 21
2 votes
0 answers
62 views

Differential equation: $f=f'f''f'''...$

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Max
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0 votes
1 answer
44 views

How to recover the frequency difference and phase shift between a square wave and a periodic integral operator?

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Srini
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0 answers
14 views

Adjoint of the second derivative operator with a point condition

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SanderSalt
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1 vote
0 answers
58 views

Feedback on a numerical integration formula

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Munchrr
  • 289
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0 answers
15 views

Quotients of ideals and isomorphism

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Steppenwolf
  • 503
1 vote
2 answers
1k views

Cauchy-Schwartz inequality in a convolution

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8 votes
1 answer
661 views

How do we define a measure of discontinuity which gives what I want?

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Arbuja
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1 vote
1 answer
48 views

integral equality

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José Carlos Santos
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8 votes
2 answers
267 views

Evaluate : $\int^1_{-1} \frac{\arctan(ax)}{x+1}\ln\left({\frac{1+x^2}{2}}\right) dx $

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Svyatoslav
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15 votes
5 answers
2k views

Determine the area of the equilateral triangle.

Jean Marie's user avatar
Jean Marie
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5 votes
1 answer
61 views

Existence of at least one injective skew-Hermitian operator

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Ryszard Szwarc
  • 45.3k
4 votes
1 answer
93 views

Proving that $e^{t/2}\cos(W_t)$ is a martingale.

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Mr. Gandalf Sauron
  • 17.2k
0 votes
1 answer
55 views

Closure of probability distributions on an open set vs probability distributions on the closure of an open set

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John Dawkins
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1 vote
0 answers
27 views

Behavior of zero morphisms and directed colimits

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I.A.S. Tambe
  • 2,879
4 votes
1 answer
43 views

Does the norm decreases, along the limit on compactly embedded Banach subspace?

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Shuhao Cao
  • 19.7k
12 votes
3 answers
680 views

Existence of Jordan curves between a compact and an open set

Daniel Smania's user avatar
Daniel Smania
  • 5,008
1 vote
0 answers
177 views

Covering of a topological space

Paul Frost's user avatar
Paul Frost
  • 88.9k
0 votes
0 answers
40 views

Some questions about (the existence of) a power set

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ducbadatcs
  • 731
1 vote
1 answer
954 views

Characterization of measurable sets in terms of open and compact sets

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CommunityBot
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2 votes
0 answers
104 views

About a step in my proof of the implicit function theorem

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ILikeMathematics
  • 324
1 vote
0 answers
47 views

Euler product over all positive integers

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Lorenzo Alvarado
  • 91
0 votes
2 answers
26 views

Contradiction in the Usual Definition of Homogeneous Solutions for LCCDEs

Ted's user avatar
Ted
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0 votes
0 answers
44 views

Covering the unit sphere with bars of fixed width and bounded overlap

Paul Frost's user avatar
Paul Frost
  • 88.9k
-1 votes
1 answer
62 views

Exercise on smooth functions

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Tveltzel
  • 442
2 votes
1 answer
48 views

Sequence of convergent Laplace transforms on an open interval corresponding to a tight sequence of random variables

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P. P. Tuong
  • 1,508
1 vote
1 answer
50 views

Is this an extraspecial group? Why?

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Vitor
  • 801
1 vote
1 answer
26 views

Probability distribution of the Fourier transform of a Gaussian process

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user110311
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0 votes
2 answers
51 views

Find the limit of the decreasing and bounded sequence

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Jack D'Aurizio
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0 votes
1 answer
50 views

"Integral of a pullback 2-form over a submanifold of $S^2 \times S^2$ is always zero"

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user1363745
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0 votes
1 answer
74 views

How to scale matrix rows so the sum of each column has a similar value?

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Rodrigo de Azevedo
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5 votes
0 answers
185 views

A discrete probability problem

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aw45600
  • 91
2 votes
1 answer
893 views

Is there a branch of mathematics which studies functions of functions?

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CommunityBot
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10 votes
1 answer
466 views

Hereditarily locally connected spaces

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Alex Ravsky
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0 votes
0 answers
51 views

Help for The approximation of the product expression

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Euass
  • 81
0 votes
0 answers
69 views

Probability of an oil tank catching on fire

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S.G
  • 13
1 vote
1 answer
33 views

Transition function of a hyperbolic atlas.

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Lee Mosher
  • 136k
0 votes
0 answers
67 views

Classical theorem which cannot be modified to be proven constructively

BoZhang's user avatar
BoZhang
  • 509
2 votes
1 answer
1k views

why value of Trigonometric ratios of angle and its reference angle are same?

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CommunityBot
  • 1
2 votes
1 answer
348 views

Prove that $\sum\limits_{cyc}\frac{1}{\sqrt{a^2+ab+b^2}}\geq\frac{2}{\sqrt{ab+ac+bc}}+\sqrt{\frac{a+b+c}{3(a^3+b^3+c^3)}}$

Another User's user avatar
Another User
  • 5,557
1 vote
1 answer
101 views

Does the first positive zero $>1$ of $\frac{\sin(\pi x)}{\prod_{k=0}^n\sin\frac{\pi x}{p_k}}$, with $p_k$ the $(k+1)$-th prime, yield the next prime?

davidlowryduda's user avatar
davidlowryduda♦
  • 94.6k
1 vote
2 answers
640 views

On Showing that $\mathbb{Z}[x]$ is not a Principal Ideal Domain

Duong Ngo's user avatar
Duong Ngo
  • 2,289
4 votes
1 answer
52 views

Boundedness of a certain Hölder coefficient

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Equations
  • 141
1 vote
1 answer
880 views

Drawing a Cayley table and finding a subgroup of H

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CommunityBot
  • 1
2 votes
1 answer
59 views

Proving that recursivly defined functions defined using $\Delta$-formulas are representable

redib's user avatar
redib
  • 21
8 votes
1 answer
171 views

Complicated trigonometric integral with parameters $\alpha$ and $\beta$, apparently with a simple closed form (comes from a probability question)

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Blue
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0 votes
0 answers
43 views

Having issues with finding 2 points using geometry and linear algebra

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Vasili
  • 11.6k
0 votes
0 answers
21 views

Symmetric (under the swapping) recursions for Stirling numbers of both kinds

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Notamathematician
  • 343
5 votes
0 answers
130 views

For all triangle prove that $\sum\limits_{cyc}\frac{bc}{a^4+2b^2c^2}\leq\frac{3}{a^2+b^2+c^2}$

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River Li
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0 votes
0 answers
25 views

Sheaf supported on a closed subset

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Peter Griffin
  • 184
0 votes
0 answers
22 views

Algorithm for listing minimal directed cuts and minimal dijoins in SageMath

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user1671795
  • 41
0 votes
0 answers
16 views

Real matrix inverse of complex vector

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Bubaya
  • 2,428
1 vote
0 answers
36 views

Fast reduction modulo some power

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minmax
  • 366
0 votes
0 answers
41 views

Explanation proof of the lemma for Besicovith's theorem

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Samuele Simeoni
  • 31
0 votes
0 answers
10 views

Does Metropolis-Hastings guarantee the convergence of densities that are induced by deterministic, invertible transformations?

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GDGDJKJ
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1 vote
1 answer
35 views

The space of continuous functions from a compact & metrizable space to a Polish space is Polish

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Hanno
  • 6,891
6 votes
0 answers
1k views

Euclidean Neighbourhoods Retracts and Deformation Retracts

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RIPAN DAS
  • 123
1 vote
1 answer
45 views

Value of a function when approaching a branch cut from different directions

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Jayanth R Varma
  • 3,398
-2 votes
0 answers
125 views

What should I name this concept? Continuous set?

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Asaf Karagila♦
  • 406k
3 votes
2 answers
79 views

Proof that a monic polynomial with $|F(0)| \ge 1$ has max modulus at least 2 on the unit circle

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user1673563
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1 vote
3 answers
156 views

When do we need use the rigorous Sequence definition as functions

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peek-a-boo
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0 answers
25 views

Non-symmetric notion of "coprimality" for ideals

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Geoffrey Trang
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