User JJR - Mathematics Stack Exchange

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	1,068 reputation	bio	website		visits	member for	10 months
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2

votes

3

answers

494

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Proof With and Without Truth Tables

logic

aug 30 at 12:15 Marc van Leeuwen 23.6k

2

votes

2

answers

222

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Proving lack of convergence in $\sup$-norm

homework real-analysis

aug 27 at 14:08 BenjaLim 16.6k

1

2

votes

1

answer

81

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Sequence of $C^1[0,1]$ functions $(f_n) \to f$ but $f \notin C^1[0,1]$

real-analysis sequences-and-series

aug 23 at 19:49 timur 6,216

2

votes

3

answers

588

views

Proving that a bounded, continuous function has a supremum

real-analysis sequences-and-series

aug 21 at 18:35 JJR 1,068

2

votes

4

answers

195

views

Proving an Integral Theorem

real-analysis

aug 20 at 6:59 Chris's wise sister 11.5k

2

votes

1

answer

120

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Proving a Riemann integral theorem

real-analysis

aug 18 at 16:21 Argha 1,538

1

2

votes

2

answers

302

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Proof of uniform continuity of $\frac{1}{x}$

real-analysis

aug 17 at 18:05 tomasz 6,894

2

votes

2

answers

106

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Proving a continuity inequality

real-analysis continuity

aug 16 at 20:31 Michael Hardy 47.7k

2

votes

2

answers

168

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Proof of Non-Ordering of Complex Field

proof-strategy proof-writing ordered-fields

aug 12 at 17:31 JJR 1,068

1

vote

0

answers

19

views

How to write down the maximal subgroups of $GL(9, \mathbb{C})$

reference-request representation-theory lie-groups

may 14 at 15:30 JJR 1,068

1

vote

1

answer

45

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Weights versus roots

representation-theory

apr 28 at 20:41 Alistair Savage 1,317

1

vote

2

answers

26

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Computing eigenvalues for $\mathrm{Sym}^2(\mathrm{Sym}^3 V))$ for $V = \Bbb C^2$

representation-theory eigenvalues tensor-products symmetric-polynomials

apr 27 at 19:51 Marc van Leeuwen 23.6k

1

vote

0

answers

23

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Branching rule restriction to $\mathrm{O}_9 \Bbb C$ from $\mathrm{GL}_9 \Bbb C$

representation-theory tensor-products symmetric-functions

apr 27 at 3:15 JJR 1,068

1

vote

0

answers

65

views

American undergraduate applying overseas

soft-question

feb 21 at 20:49 JJR 1,068

1

vote

1

answer

52

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Cardano's Formulas help

galois-theory

jan 14 at 20:01 André Nicolas 160k

1

vote

2

answers

131

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Is the conjugation map always an isomorphism?

abstract-algebra

dec 4 at 15:33 amWhy 53.9k

1

vote

1

answer

78

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For $G$ a group, if $|G| = n$, $n$ composite, will $G$ have a proper subgroup?

abstract-algebra

dec 4 at 0:45 user44441 161

1

vote

1

answer

49

views

How to prove that $\mathrm{GL}_2(\Bbb Z_2)$ has only six subgroups

abstract-algebra

nov 28 at 21:04 joriki 92.1k

1

vote

2

answers

77

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Trouble with this multiplication table

homework abstract-algebra

nov 25 at 23:43 Lubin 5,796

2

1

vote

3

answers

165

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Problems like the handshake problem

reference-request recreational-mathematics problem-solving

nov 23 at 15:02 amWhy 53.9k

1

vote

1

answer

53

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Is this true: $A \le N_G(B) \not \Rightarrow B \trianglelefteq A$?

abstract-algebra

nov 3 at 18:20 Alexander Gruber 15.1k

1

vote

2

answers

116

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Computing the mean of a stationary distribution for Wright-Fisher model

homework probability stochastic-processes

sep 20 at 23:05 Byron Schmuland 15.3k

1

vote

1

answer

78

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Proving a non-stopping time

stochastic-processes markov-chains

sep 15 at 3:47 JJR 1,068

1

vote

1

answer

133

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Proving that $X_n$ is (or is not) a Markov Chain

probability-theory stochastic-processes

sep 5 at 0:17 Taylor 83

1

vote

1

answer

29

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How to show that the $k$th return to $y$ is a stopping time

probability stochastic-processes

sep 4 at 23:09 Byron Schmuland 15.3k

1

vote

6

answers

527

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Proving that $a,n$ and $b, n$ relatively prime implies $ab,n$ relatively prime

homework elementary-number-theory

sep 1 at 18:11 JJR 1,068

1

vote

1

answer

220

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Convergence in $\sup$ norm $\Rightarrow$ Cauchy in $\sup$

real-analysis sequences-and-series

aug 26 at 20:00 Robert Israel 86k

1

vote

1

answer

105

views

Proving pointwise convergence to a “Dirichlet-like” function

real-analysis convergence

aug 24 at 12:15 JJR 1,068

1

vote

2

answers

96

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$|P(x)|$ differentiable at a root $x_0$

polynomials

aug 19 at 14:47 Henning Makholm 53.5k

1

vote

3

answers

722

views

Proving that a sequence is Cauchy

real-analysis sequences-and-series

aug 15 at 14:28 Brian M. Scott 153k

JJR

69 Questions