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A question about co-exponentials

notation category-theory

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Why does Frank Adams demand a finite CW-complex?

algebraic-topology category-theory homotopy-theory

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The relation between logic and algebra.

abstract-algebra logic

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What Is The Limit Of The Sequence: $\frac{n^3}{{((3n)!)^\frac{1}{n}}}$

calculus real-analysis sequences-and-series

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Explain/illustrate Goedel's theorems and possible implications to non-mathematicians

logic education philosophy incompleteness foundations

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104

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What kinds of structures support integration?

calculus real-analysis general-topology

Nov 30 '13 at 21:37 Sebastian Garrido 453

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Is $\mathbb{R}/\mathbb{Q}$ an interesting group? [duplicate]

measure-theory reference-request soft-question

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Good resource to learn transfinite induction and/or recursion?

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538

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Are there logics without modus ponens?

logic computer-science formal-proofs formal-systems nonclassical-logic

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Graduate Level Mathematical Logic Textbooks

logic reference-request model-theory computability proof-theory

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140

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“Quantifying” over properties and “operations” in ZFC and transfinite recursion: clarifying confusion

set-theory first-order-logic foundations transfinite-recursion

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Hatcher Question 0.27

algebraic-topology homotopy-theory

Nov 1 '18 at 11:19 Andrews 2,114

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Let $\mathcal{D}$ be an additive category, and $f$ a morphism that is both monic and epic. Must $f$ be an isomorphism?

category-theory homological-algebra derived-categories

Feb 16 '17 at 22:53 Kevin Carlson 37.9k

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925

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Meaning of the antipode in Hopf algebras?

abstract-algebra representation-theory hopf-algebras coalgebras

Oct 23 '16 at 0:14 Community♦ 1

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Example of discrete subgroup of $\mathbb{R}^2$ where image of $X$ under 1st projection isn't discrete subset of $\mathbb{R}$?

abstract-algebra group-theory

Oct 19 '16 at 1:18 Pavel Čoupek 5,596

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Intuition for the chain homotopy of Poincaré lemma.

algebraic-topology differential-topology homology-cohomology

Oct 8 '16 at 18:39 arkeet 5,585

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Squeeze/Sandwich Theorem Involving $n^{th}$ root: $\lim _{ n\rightarrow \infty }{\left(3^n+1\right)}^{\frac 1n}$

calculus sequences-and-series limits

Jul 29 '16 at 18:50 Community♦ 1

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111

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For any 7 different real numbers, there are among them two numbers x and y such that $0<\frac{x-y}{1+xy} < √3$

number-theory

Apr 24 '15 at 23:26 TonyK 48.7k

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Maximal homogeneous ideals of a graded $k$-algebra.

abstract-algebra algebraic-geometry commutative-algebra graded-rings

Aug 13 '14 at 6:55 Jared 28.3k

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302

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Can we prove the existence of a gcd in $\mathbb Z$ without using division with remainder?

abstract-algebra divisibility integers

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Why is there only one group of order $n$ for some non-primes?

group-theory elementary-number-theory

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How are $G$-modules and linear group actions different

abstract-algebra group-theory modules representation-theory group-actions

Jan 7 '16 at 19:15 Jeremy Rickard 18.5k

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Group such that Aut(G) = H and Aut(H) = G

group-theory

Mar 23 '16 at 22:18 Rico 324

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596

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“let” vs “suppose” vs “if” and the contrapositive

proof-writing propositional-calculus

Sep 9 '16 at 16:24 Community♦ 1

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193

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illustrative book of differential geometry

differential-geometry reference-request differential-topology

Oct 1 '16 at 17:55 L.F. Cavenaghi 3,910

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114

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Does there exist a model of $ZF¬C$ in which there is a function on $\mathbb R$ which is sequentially continuous at a point where it is not continuous? [duplicate]

real-analysis continuity set-theory axiom-of-choice

Jun 20 '15 at 20:00 Asaf Karagila♦ 323k

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178

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Looking for a “Guide for the Perplexed by Low-dimensional Topology”

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Proving whether the following are groups or not.

group-theory inverse

Oct 19 '15 at 2:43 letsmakemuffinstogether 1,544

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328

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Is there an English version of Johann Bernoulli's integral calculus lectures?

calculus reference-request soft-question math-history

Jun 6 '17 at 13:33 Immortal Player 713

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Let $T\colon \Bbb{R}^5\to\Bbb{R}^5$ be a linear operator such that $T^4\neq 0$ but $T^5=0$. What is the rank of $T^2$?

linear-algebra eigenvalues-eigenvectors linear-transformations

Oct 19 '16 at 0:56 la flaca 2,231

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309 Favorites

A question about co-exponentials

Why does Frank Adams demand a finite CW-complex?

The relation between logic and algebra.

What Is The Limit Of The Sequence: $\frac{n^3}{{((3n)!)^\frac{1}{n}}}$

Explain/illustrate Goedel's theorems and possible implications to non-mathematicians

What kinds of structures support integration?

Is $\mathbb{R}/\mathbb{Q}$ an interesting group? [duplicate]

Good resource to learn transfinite induction and/or recursion?

Are there logics without modus ponens?

Graduate Level Mathematical Logic Textbooks

“Quantifying” over properties and “operations” in ZFC and transfinite recursion: clarifying confusion

Hatcher Question 0.27

Let $\mathcal{D}$ be an additive category, and $f$ a morphism that is both monic and epic. Must $f$ be an isomorphism?

Meaning of the antipode in Hopf algebras?

Example of discrete subgroup of $\mathbb{R}^2$ where image of $X$ under 1st projection isn't discrete subset of $\mathbb{R}$?

Intuition for the chain homotopy of Poincaré lemma.

Squeeze/Sandwich Theorem Involving $n^{th}$ root: $\lim _{ n\rightarrow \infty }{\left(3^n+1\right)}^{\frac 1n}$

For any 7 different real numbers, there are among them two numbers x and y such that $0<\frac{x-y}{1+xy} < √3$

Maximal homogeneous ideals of a graded $k$-algebra.

Can we prove the existence of a gcd in $\mathbb Z$ without using division with remainder?

Why is there only one group of order $n$ for some non-primes?

How are $G$-modules and linear group actions different

Group such that Aut(G) = H and Aut(H) = G

“let” vs “suppose” vs “if” and the contrapositive

illustrative book of differential geometry

Does there exist a model of $ZF¬C$ in which there is a function on $\mathbb R$ which is sequentially continuous at a point where it is not continuous? [duplicate]

Looking for a “Guide for the Perplexed by Low-dimensional Topology”

Proving whether the following are groups or not.

Is there an English version of Johann Bernoulli's integral calculus lectures?

Let $T\colon \Bbb{R}^5\to\Bbb{R}^5$ be a linear operator such that $T^4\neq 0$ but $T^5=0$. What is the rank of $T^2$?