(2,3,7) triangle group

E262443

The (2,3,7) triangle group is a Fuchsian group generated by reflections in the sides of a hyperbolic triangle with angles π/2, π/3, and π/7, notable for its connection to highly symmetric structures such as the Klein quartic.

All labels observed (4)

Label Occurrences
(2,3,7) triangle group canonical 3
triangle group (2,3,7) 2
(2,3,7) von Dyck group 1

How this entity was disambiguated

Statements (41)

Predicate Object
instanceOf Fuchsian group
discrete subgroup of PSL(2,R)
triangle group
actsOn hyperbolic plane
hasAreaOfFundamentalTriangle π(1 - 1/2 - 1/3 - 1/7)
hasCategory Riemann surface theory
geometric group theory
hyperbolic geometry
hasCoxeterDiagram triangle with edge labels 2,3,7
hasCoxeterPresentation ⟨ r1,r2,r3 | r1² = r2² = r3² = (r1r2)² = (r2r3)³ = (r1r3)⁷ = 1 ⟩
hasFundamentalDomain hyperbolic triangle with angles π/2, π/3, π/7
hasGeneratorsOfOrder 2
3
7
hasIndexInOrientationPreservingSubgroup 2
hasMinimalSumOfReciprocals among hyperbolic triangle groups
hasOrbifoldNotation *237
hasOrientationPreservingOrbifoldNotation 237
hasOrientationPreservingQuotient PSL(2,7)
automorphism group of the Klein quartic
hasOrientationPreservingSubgroup (2,3,7) von Dyck group
hasPresentation ⟨ x,y,z | x² = y³ = z⁷ = xyz = 1 ⟩ (orientation-preserving subgroup)
hasQuotientOrbifold sphere with cone points of orders 2, 3, and 7
hasSignature (2,3,7)
hasTriangleAngle π/2
π/3
π/7
hasType cofinite Fuchsian group
isArithmetic true
isAssociatedWith Hurwitz surfaces
isCoxeterGroup true
isGeneratedBy reflections in the sides of a hyperbolic triangle
isHyperbolicTriangleGroup true
isMaximalHyperbolicTriangleGroup true
isNamedAfter its triangle angle orders 2, 3, and 7
isRelatedTo Hurwitz bound 84(g−1)
Klein quartic
isUsedIn construction of highly symmetric Riemann surfaces
theory of Hurwitz groups
satisfies 1/2 + 1/3 + 1/7 < 1
uniformizes Klein quartic

How these facts were elicited

Referenced by (7)

Full triples — surface form annotated when it differs from this entity's canonical label.

Klein quartic relatedToTriangleGroup (2,3,7) triangle group
Hurwitz bound on automorphism groups of curves relatedConcept triangle group (2,3,7)
linked to: (2,3,7) triangle group
(2,3,7) triangle group hasOrientationPreservingSubgroup (2,3,7) von Dyck group
linked to: (2,3,7) triangle group
Hermann Amandus Schwarz hasNotableConcept Schwarz triangle
linked to: (2,3,7) triangle group
Hurwitz surface relatedTo triangle group (2,3,7)
subject linked to: Hurwitz surfaces
linked to: (2,3,7) triangle group
Hurwitz surface uniformizedBy (2,3,7) triangle group
subject linked to: Hurwitz surfaces
Hurwitz group relatedTo (2,3,7) triangle group