Ivan Shishkin, Birch Grove

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1–75 of 273 concepts

Empty set

Stub

DefinitionSet theory2 incoming linksExercises: 0

updated 10/25/2026

Topological space

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DefinitionTopology17 incoming linksExercises: 1

updated 10/24/2026

Topological manifold

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DefinitionTopology2 incoming linksExercises: 2

updated 10/19/2026

Hausdorff space

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DefinitionTopology1 incoming linkExercises: 2

updated 10/19/2026

Triangle

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DefinitionGeometry1 incoming linkExercises: 0

updated 10/19/2026

Set

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DefinitionSet theory18 incoming linksExercises: 0

updated 10/19/2026

Right triangle

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DefinitionOther1 incoming linkExercises: 0

updated 10/19/2026

Euclidean division

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DefinitionNumber theory1 incoming linkExercises: 2

updated 10/18/2026

Fraction

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DefinitionGeneral algebra2 incoming linksExercises: 2

updated 10/15/2026

Compact space

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DefinitionTopology2 incoming linksExercises: 3

updated 10/14/2026

Second-countable space

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DefinitionTopology1 incoming linkExercises: 2

updated 10/14/2026

Euclid’s lemma

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TheoremNumber theory0 incoming linksExercises: 0

updated 10/14/2026

Subgroup

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DefinitionGeneral algebra6 incoming linksExercises: 2

updated 10/13/2026

Monic polynomial

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DefinitionGeneral algebra4 incoming linksExercises: 0

updated 10/7/2026

Field homomorphism

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DefinitionGeneral algebra3 incoming linksExercises: 2

updated 10/2/2026

Field extension

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DefinitionField10 incoming linksExercises: 2

updated 10/2/2026

pp-adic valuation

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DefinitionOther4 incoming linksExercises: 4

updated 10/1/2026

Transpose of a matrix

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DefinitionGeneral algebra2 incoming linksExercises: 4

updated 10/1/2026

KK-automorphism

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DefinitionField4 incoming linksExercises: 1

updated 9/30/2026

Path-connected space

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DefinitionTopology4 incoming linksExercises: 2

updated 9/28/2026

Limit

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DefinitionTopology1 incoming linkExercises: 1

updated 9/28/2026

Kernel of an action; faithful, free, transitive, simply transitive actions

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DefinitionGeneral algebra0 incoming linksExercises: 0

updated 9/27/2026

Group action

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DefinitionGeneral algebra3 incoming linksExercises: 0

updated 9/27/2026

Even number

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DefinitionNumber theory2 incoming linksExercises: 1

Even integer

updated 9/26/2026

Symmetric matrix

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DefinitionLinear algebra2 incoming linksExercises: 3

updated 9/24/2026

Function

StubEdited since review

DefinitionMathematical formalism10 incoming linksExercises: 0

Map

updated 9/24/2026

Open set

Reviewed

DefinitionTopology7 incoming linksExercises: 0

Open subset

updated 9/24/2026

Group

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DefinitionGeneral algebra23 incoming linksExercises: 3

updated 9/17/2026

Real number

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DefinitionOther4 incoming linksExercises: 0

updated 9/16/2026

Integration by parts

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DefinitionRiemann integration2 incoming linksExercises: 3

updated 9/15/2026

Interval

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DefinitionReal analysis0 incoming linksExercises: 0

updated 9/15/2026

Surjective map

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DefinitionOther2 incoming linksExercises: 1

updated 9/15/2026

Injective map

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DefinitionOther1 incoming linkExercises: 3

updated 9/15/2026

Characteristic polynomial of a matrix

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DefinitionLinear algebra2 incoming linksExercises: 1

updated 9/15/2026

Vector space

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DefinitionLinear algebra8 incoming linksExercises: 1

updated 9/13/2026

Fundamental group

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DefinitionAlgebraic topology2 incoming linksExercises: 0

updated 9/13/2026

Subset

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DefinitionMathematical formalism10 incoming linksExercises: 3

updated 9/13/2026

Metric

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DefinitionTopology6 incoming linksExercises: 3

Distance function

updated 9/11/2026

Prime number

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DefinitionNumber theory10 incoming linksExercises: 2

updated 9/11/2026

Convex set

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DefinitionGeneral algebra5 incoming linksExercises: 1

updated 9/10/2026

Geometric mean

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DefinitionReal analysis1 incoming linkExercises: 0

updated 9/9/2026

Even function

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DefinitionOther2 incoming linksExercises: 4

updated 9/8/2026

Connected graph

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DefinitionCombinatorics1 incoming linkExercises: 1

updated 9/6/2026

Intermediate value theorem

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TheoremReal function1 incoming linkExercises: 2

updated 9/4/2026

Simple root

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DefinitionGeneral algebra3 incoming linksExercises: 0

updated 9/1/2026

Preimage

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DefinitionSet theory1 incoming linkExercises: 1

updated 9/1/2026

Symmetry

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Intuitive notionGroup0 incoming linksExercises: 0

updated 9/1/2026

Symmetric positive matrix

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DefinitionOther2 incoming linksExercises: 1

updated 9/1/2026

Trace

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DefinitionGeneral algebra2 incoming linksExercises: 0

updated 9/1/2026

Complex number

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DefinitionGeneral algebra2 incoming linksExercises: 2

updated 8/31/2026

Matrix

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DefinitionLinear algebra8 incoming linksExercises: 2

updated 8/31/2026

Norm

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DefinitionTopology2 incoming linksExercises: 5

updated 8/30/2026

Image of a map

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DefinitionSet theory2 incoming linksExercises: 0

updated 8/30/2026

Eigenvalue of a matrix

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DefinitionLinear algebra3 incoming linksExercises: 0

updated 8/29/2026

Sylow pp-subgroup

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DefinitionGroup0 incoming linksExercises: 0

updated 8/29/2026

pp-group

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DefinitionOther1 incoming linkExercises: 1

updated 8/29/2026

Operation

Reviewed

DefinitionGeneral algebra5 incoming linksExercises: 0

updated 8/28/2026

Commutative operation

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DefinitionGeneral algebra2 incoming linksExercises: 0

updated 8/28/2026

Scalar

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DefinitionLinear algebra1 incoming linkExercises: 0

updated 8/28/2026

Orthogonal matrix

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DefinitionGeneral algebra2 incoming linksExercises: 0

updated 8/27/2026

Odd function

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DefinitionReal function3 incoming linksExercises: 5

updated 8/26/2026

Spectral Theorem

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TheoremEuclidean vector space4 incoming linksExercises: 2

updated 8/26/2026

Cardinal

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DefinitionMathematical formalism1 incoming linkExercises: 2

updated 8/24/2026

Normal subgroup

Stub

DefinitionGeneral algebra2 incoming linksExercises: 1

updated 8/23/2026

Order of an element of a group

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DefinitionGroup1 incoming linkExercises: 1

updated 8/23/2026

Proper subset

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DefinitionMathematical formalism2 incoming linksExercises: 0

strict subset

updated 8/22/2026

Cross-multiplication

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DefinitionGeneral algebra1 incoming linkExercises: 0

updated 8/21/2026

Residue theorem

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TheoremComplex analysis0 incoming linksExercises: 1

updated 8/21/2026

Metric space

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DefinitionTopology3 incoming linksExercises: 0

updated 8/20/2026

Divisibility

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DefinitionGeneral algebra3 incoming linksExercises: 0

updated 8/20/2026

Element expressible by radicals

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DefinitionGeneral algebra1 incoming linkExercises: 0

updated 8/20/2026

Path homotopy

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DefinitionTopology1 incoming linkExercises: 1

updated 8/17/2026

Radical of an ideal

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DefinitionGeneral algebra1 incoming linkExercises: 0

updated 8/16/2026

Normed vector space

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DefinitionGeneral algebra3 incoming linksExercises: 0

updated 8/16/2026

Parabola

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DefinitionGeneral algebra1 incoming linkExercises: 0

updated 8/15/2026