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active 7 featured hot week month

1

vote

1

answer

31

views

Are there graphs for which infinitely many numbers cannot be the sum of the labels of its vertices?

nt.number-theory co.combinatorics graph-theory

modified 4 mins ago Bernardo Recamán Santos 766

-1

votes

1

answer

20

views

Does this function belong to $L^2(\mathbb{D})$?

real-analysis ds.dynamical-systems sobolev-spaces

answered 3 mins ago Alexandre Eremenko 37.9k

1

vote

1

answer

72

views

Pencil of ellipses

mg.metric-geometry

modified 17 mins ago Alexandre Eremenko 37.9k

0

votes

1

answer

58

views

Web interface for GAP (or other computer algebra system dealing with finite groups)?

gr.group-theory rt.representation-theory finite-groups computer-algebra

answered 2 hours ago Derek Holt 21.3k

1

vote

0

answers

51

views

A continuity lemma for manifold

at.algebraic-topology manifolds

modified 1 hour ago DyNaMic 35

2

votes

0

answers

72

views

Is there a closed form for $\int_0^\infty\frac{tanh^3(x)}{x^2}dx$?

ca.analysis-and-odes integration riemann-zeta-function closed-form-expressions

modified 1 hour ago Liviu Nicolaescu 22.2k

4

votes

0

answers

68

views

Self-equivalences of the stable homotopy category

stable-homotopy stable-homotopy-category

modified 1 hour ago Marco Vergura 111

0

votes

0

answers

20

views

Is it true that $\bigcap_{V}\overline{L_V}=\left\{\lim_{U\to \{e\}}I_U \right\}$

haar-measure

asked 3 hours ago Ergin Suer 104

-1

votes

0

answers

18

views

What are the Cartesian coordinates of equidistant (arc-length) points on a curvy surjective line? [on hold]

ag.algebraic-geometry dg.differential-geometry geometry curves

asked 2 hours ago M.A. 1

5

votes

2

answers

207

views

In the group ring $\mathbb{Z}_p [G]$, what elements satisfy $(\sum a_g g)^p = \sum a_g g^p$?

gr.group-theory ra.rings-and-algebras group-rings

answered 1 hour ago Will Sawin 52.2k

0

votes

0

answers

28

views

How to compare convergence of two equations for the arctangent function?

limits-and-convergence

asked 3 hours ago Freedom Math 1

3

votes

0

answers

46

views

Asymptotics of number-theory functions and it's averages

nt.number-theory analytic-number-theory

asked 5 hours ago Pavel Kozlov 113

-1

votes

0

answers

97

views

about infinitely many bounded gaps between primes [on hold]

nt.number-theory real-analysis analytic-number-theory

modified 1 hour ago C Marius 15

1

vote

0

answers

30

views

correspondence between finite abelian extensions and congruence subgroups

class-field-theory

asked 5 hours ago user110832 6

6

votes

0

answers

57

views

The existence of the Drinfeld shtuka function

ag.algebraic-geometry reference-request divisors jacobians

asked 5 hours ago Stabilo 289

1

vote

0

answers

22

views

Computing distribution of non-identical coin flips

computational-complexity probability-distributions

asked 5 hours ago Bill Bradley 1,552

4

votes

0

answers

50

views

On tetrahedral Artin representation

automorphic-forms galois-representations

modified 4 hours ago Ivan Izmestiev 2,079

0

votes

1

answer

42

views

Closed form of an integral involving exponential and trigonometric functions

real-analysis

answered 3 hours ago Robert Israel 34k

0

votes

0

answers

18

views

In a short time $0<t<T$, does the $C^{1,\alpha}$ norm of mean curvature flow depend only on $T$ and the $C^{1,\alpha}$ norm of initial surface?

reference-request geometric-analysis

asked 4 hours ago student 339

3

votes

1

answer

64

views

Median and mean of the sample mean of i.i.d. log-normal

pr.probability st.statistics probability-distributions inequalities

modified 1 hour ago Hans 488

1

vote

0

answers

76

views

Frobenius number of a local ring

nt.number-theory ac.commutative-algebra

modified 3 hours ago Pham Hung Quy 1,779

3

votes

1

answer

249

views

Smooth manifold with affine structure: aspherical?

dg.differential-geometry homotopy-theory sg.symplectic-geometry

modified 12 hours ago Francesco Polizzi 39.6k

2

votes

0

answers

38

views

An identity of operator norms and de Leeuw's theorem

fa.functional-analysis fourier-analysis harmonic-analysis operator-theory

modified 7 hours ago Right 62

2

votes

0

answers

55

views

Limitations of determinacy hypotheses in ZFC

set-theory determinacy

asked 9 hours ago Dan Nielsen 315

-1

votes

0

answers

28

views

Probability - Variance of the birthday problem [on hold]

pr.probability

asked 8 hours ago fradeb 1

-2

votes

0

answers

15

views

General equation of a linear curve with sudden pulses at regular intervals [on hold]

curves

asked 6 hours ago user110828 1

2

votes

2

answers

307

views

Anyone recognizing or knowing how to solve this integral?

integration

modified 8 hours ago Gerald Edgar 23.8k

1

vote

0

answers

43

views

Using the Bruhat-Tits tree for unitary groups

algebraic-groups lattices trees

asked 11 hours ago Desiderius Severus 855

1

vote

1

answer

70

views

Goldman Lie algebra of a bordered surface vs. a closed surface?

gr.group-theory gt.geometric-topology lie-algebras mapping-class-groups string-topology

answered 6 hours ago Sean Lawton 2,532

2

votes

1

answer

154

views

Must a curve containing $(d^2+3d)/2$ lattice points contain another?

ag.algebraic-geometry

modified 16 hours ago Douglas Zare 23.8k

-2

votes

0

answers

44

views

Harnack Inequality and Geometric Analysis [on hold]

dg.differential-geometry geometric-analysis

asked 12 hours ago DLIN 172

3

votes

0

answers

43

views

Sequence of diffusions

pr.probability stochastic-processes stochastic-calculus stochastic-diff-equations

modified 5 hours ago user74045 72

52

votes

18

answers

7k

views

When has discrete understanding preceded continuous?

ho.history-overview big-picture discrete-mathematics continuity

modified Jun 2 at 21:15 Matt F. 4,015

19

votes

2

answers

277

views

Morphism from a surface group to a symmetric group, lifted to the braid group

at.algebraic-topology gr.group-theory gt.geometric-topology homotopy-theory

modified 6 hours ago Ian Agol 39.7k

3

votes

1

answer

84

views

Continuation (Extension) of Harmonic Functions

ap.analysis-of-pdes real-analysis riemannian-geometry differential-equations elliptic-pde

modified 14 hours ago Alexandre Eremenko 37.9k

4

votes

0

answers

94

views

Do homological holes with unit coefficients correspond to polyhedra?

mg.metric-geometry homology

modified 5 hours ago GMB 431

10

votes

1

answer

361

views

exponential sum over variety

ag.algebraic-geometry exponential-sums arithmetic-variety

answered yesterday Will Sawin 52.2k

15

votes

4

answers

529

views

Integer matrices whose determinant equals their norm

nt.number-theory linear-algebra matrices diophantine-equations

modified 21 hours ago Geoff Robinson 26k

4

votes

1

answer

97

views

Are two recursive well-orderings with the same order type recursively isomorphic?

computability-theory ordinal-numbers

modified 21 hours ago Joel David Hamkins 139k

0

votes

0

answers

209

views

On a number theoretic problem

nt.number-theory analytic-number-theory arithmetic-progression exponential-sums trigonometric-sums

modified 12 hours ago Turbo 2,741

5

votes

3

answers

303

views

Identity involving an improper integral (with geometric application)

dg.differential-geometry ca.analysis-and-odes integration special-functions curves-and-surfaces

answered yesterday mickep 131

3

votes

1

answer

207

views

Grothendieck topos and logic

ct.category-theory lo.logic higher-category-theory topos-theory

answered 6 hours ago godelian 1,841

2

votes

0

answers

32

views

Substructural types, the lambda calculus, and CCCs

type-theory lambda-calculus cartesian-closed

asked 18 hours ago C. Bednarz 11

5

votes

0

answers

223

views

Every mathematical object can be determinated uniquelly by his categorical structure? [on hold]

ag.algebraic-geometry ct.category-theory complex-geometry

asked yesterday camilo 77

5

votes

1

answer

86

views

Hausdorff dimension and sigma finiteness

real-analysis measure-theory geometric-measure-theory fractals

modified 23 hours ago Mark McClure 1,330

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