Questions tagged [reference-request]
This tag is for questions seeking external references (books, articles, etc.) about a particular subject. Please do not use this as the only tag for a question.
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Is this a kind of generalized Lebesgue Differentiation Theorem?
Let $\nu$ be a $\sigma$-finite measure and let $f: X \rightarrow \mathbb{R}$ be measurable.
It's true that
$$ \dfrac{1}{\nu(G)}\int_G f d \nu \leq f(x) \mbox{ for a.a. } x \in G$$
with $G \subset X$ a ...
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Show that $\sum_{k=1}^n{2^{2k-1}\binom{2n+1}{2k}B_{2k}(0)}=n$
Lately, I've been working on a proof (whose context is not necessary to discuss) and I only need one last thing in order to finish it. To be more specific, for completeness it would suffice to show ...
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Reference on the Partition Problem's existence of a Solution
I would like to find some references on this problem
Let $I_n$ denote the set of numbers $\{1, \cdots, n\}$. Show that
given any $n$ distinct numbers $a_1, a_2, \cdots, a_n$ from the set
$I_{\frac{3n}...
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Positive, Real Roots of Bivariate Polynomial
I have a question regarding lemma 3.1 in this paper. The lemma in question is as follows
Consider the function $f(x, \lambda) = ax^3 + bx^2 + cx + d$ where $a > 0$ is
fixed but for which the ...
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O'Kineally Master Theorem and the Exponential Derivative
I was watching this video earlier and I found this method absolutely fascinating. The creator referred to the method as "O'Kineally's Method" which uses the exponential derivative $E = e^{\...
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Well-posedness result for a linear parabolic equation on torus
Consider the following linear parabolic equation in one spatial dimension for $u=u(x,t)$ on the one-dimensional torus $\mathbb{T}^1,$ meaning $x \in \mathbb{T}^1$ and $t \in (0, T]:$
$$ \partial_t u- ...
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Type theory reference including applications to multiple computer languages
I'm wondering if anyone could recommend me a good text on the application of type theory to computer languages (plural).
What I'm looking for:
Discusses formal theory in moderately-rigorous terms
...
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82
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Commutative algebra from Hungerford’s algebra [closed]
I just finished a course in abstract algebra (group theory, ring and module theory, field and Galois theory) from Hungerford’s algebra GTM. I want to study algebraic geometry, and commutative algebra ...
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Is this proof of the angle bisector theorem known?
Given a triangle $ABC$, let $D$ be the point of intersection of the side $BC$ with the bisector of the angle $A$. Then $|AB|/|AC|=|DB|/|DC|$.
This statement is known as the angle bisector theorem.
Is ...
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Is there a name for non sparse linear operators which are products of convolution-like all-but-oneunities?
Is there a name for non sparse linear operators which are products of convolution-like all-but-one unities?
I suppose I will have to apologize for the cryptic question phrasing, but I really could not ...
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Moments of Pearcy type integral
In my research I encounter Moments of Pearcy Integral
which can be written as
$$
\int_{-\infty}^{\infty}x^{n}
{\rm e}^{-ax^{4} + bx^{2} + cx}\,{\rm d}x\qquad
a > ...
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1
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138
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Seeking "900 Geometry Problems" Book – Any Leads on Its Whereabouts?
I have been on a quest to find a book titled "900 Geometry Problems" that I've heard a lot about.
Geometry is a subject I am deeply passionate about, and from what I've gathered, this book ...
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Looking for an applied mathematics book with each chapter with an epigraph from The Simpsons
I am looking for a math book. I have a small part of it in PDF (I forget where I got it from, perhaps a .edu webpage) and I'm considering buying the book. Unfortunately, the name and the author of the ...
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Reference Needed: Existence of Subsets of $\mathbb{N}$ with Specified Lower and Upper Asymptotic Densities
Could someone point me to a book or paper that states the following fact:
For any $ 0 \leq \alpha \leq \beta \leq 1 $, there exists a subset $ A \subset \mathbb{N} $ such that
$$\underline{\mathrm{d}}(...
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Quadratic Optimization with positivity, equality constraints - Literature Review?
I'm trying to solve a problem of the form $\min x^T Q x$ such that $Ax = b$ and $x_i \ge 0$ for all components $i$; $x, b$ are vectors; and $Q, A$ are matrices. In this case $Q$ is square and positive ...