User JJR - Mathematics Stack Exchange

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	1,075 reputation	bio	website		visits	member for	11 months
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1

12

votes

6

answers

415

views

Appropriate Notation: $\equiv$ versus $:=$

notation

aug 14 at 2:03 Michael Hardy 48.3k

1

8

votes

3

answers

114

views

Cardinality of the Union is less than the cardinality of the Cartesian product

set-theory cardinals

nov 26 at 20:40 Michael Greinecker♦ 12.5k

7

votes

2

answers

510

views

Why is $Q[\pi]$ not a field?

abstract-algebra

nov 1 at 1:12 Community♦ 1

6

votes

2

answers

73

views

Factoring $x^{255} -1 $ over $\Bbb F_2$

galois-theory

apr 8 at 20:17 JJR 1,075

6

votes

4

answers

123

views

Zero polynomial [duplicate]

abstract-algebra soft-question convention

sep 25 at 21:06 Davide Giraudo 56.3k

3

6

votes

1

answer

304

views

“So That” vs. “Such That”

soft-question terminology

aug 18 at 18:16 JJR 1,075

5

votes

1

answer

431

views

Convergence in probability, not almost surely

real-analysis probability-theory

nov 10 at 1:42 Henry 32.1k

2

5

votes

1

answer

506

views

Lipschitz Continuous $\Rightarrow$ Uniformly Continuous

real-analysis proof-writing continuity

aug 17 at 14:23 Brian M. Scott 155k

4

votes

1

answer

50

views

Basic identity of characters

representation-theory

feb 20 at 3:49 BenjaLim 16.8k

4

votes

5

answers

681

views

Proving that $\mu$ is $\sup S$

real-analysis sequences-and-series

aug 15 at 8:13 t.b. 43.2k

4

votes

2

answers

243

views

Format of Proof by Induction

induction proof-writing

aug 12 at 15:08 Brian M. Scott 155k

1

4

votes

5

answers

284

views

Canonical Isomorphism Between $\mathbf{V}$ and $(\mathbf{V}^)^$

linear-algebra vector-spaces

aug 6 at 11:18 Asaf Karagila 91.5k

3

votes

1

answer

33

views

How to compute the weights of $\Gamma_{3,1}$ the irrep of $\mathfrak{sl}_3\Bbb C$

combinatorics representation-theory symmetric-polynomials

apr 28 at 14:08 Alistair Savage 1,509

1

3

votes

2

answers

100

views

Subgroups of order $p$ and $p^{n-1}$ in a group of order $p^n$.

abstract-algebra group-theory finite-groups p-groups

apr 26 at 1:18 Alexander Gruber♦ 15.2k

1

3

votes

2

answers

44

views

Galois relations between subfields

galois-theory extension-field

mar 7 at 2:58 JSchlather 9,745

3

votes

1

answer

56

views

Connection between Galois trace and matrix trace

galois-theory

feb 28 at 1:21 Dimitri 446

3

votes

1

answer

46

views

Character of a permutation representation

representation-theory characters

feb 21 at 11:29 Martin Sleziak 20.3k

3

votes

2

answers

94

views

Proofs using linear congruences

modular-arithmetic

sep 15 at 3:06 lab bhattacharjee 29k

3

votes

3

answers

121

views

Proving a congruence solution is unique $\pmod {m/\gcd(c,m)}$

modular-arithmetic

sep 14 at 20:51 Community♦ 1

1

3

votes

4

answers

913

views

Last two digits of $3^{400}$

elementary-number-theory

sep 12 at 6:23 André Nicolas 162k

1

3

votes

1

answer

90

views

Checking Uniform Convergence

real-analysis

aug 23 at 13:14 JJR 1,075

3

votes

3

answers

236

views

Finding $F(x)$ so that $F'(x) = e^{-x^2}$

real-analysis integration

aug 20 at 3:10 Argon 9,276

1

3

votes

1

answer

225

views

Difference of two Cauchy Sequences

homework real-analysis sequences-and-series

aug 14 at 0:24 JJR 1,075

3

votes

4

answers

189

views

Find a sequence $\{a_n\}$ that converges to $a$ without getting “closer and closer”

homework sequences-and-series limit

aug 13 at 16:32 Community♦ 1

2

votes

0

answers

45

views

Subspaces stabilized by representations of $\mathrm O(9)$

reference-request representation-theory

apr 21 at 21:30 JJR 1,075

2

votes

3

answers

158

views

How fill in this multiplication table?

abstract-algebra

nov 26 at 3:13 Michael Hardy 48.3k

2

votes

3

answers

80

views

$S_n$ acting transitively on $\{1, 2, \dots, n\}$

abstract-algebra group-theory finite-groups permutations

nov 23 at 5:33 Alexander Gruber♦ 15.2k

1

2

votes

1

answer

97

views

Counterexamples to the following logical statements about sets

elementary-set-theory

nov 4 at 21:48 Brian M. Scott 155k

2

votes

1

answer

133

views

For $H, K$ normal subgroups of $G$ with $H \le K$, then $K/H \trianglelefteq G/H$

abstract-algebra group-theory

nov 3 at 15:49 Martin Sleziak 20.3k

2

votes

2

answers

66

views

Verifying prime factorization equivalence class

abstract-algebra relations

sep 7 at 17:52 Community♦ 1

JJR

71 Questions