Lambert series

E279122

Lambert series are special infinite series in number theory and analysis, often involving arithmetic functions and powers of a variable, introduced by Johann Heinrich Lambert and used in the study of modular forms and q-series.

All labels observed (2)

Label Occurrences
Lambert series canonical 1
Poincaré series 1

How this entity was disambiguated

Statements (47)

Predicate Object
instanceOf concept in mathematical analysis ⓘ
concept in number theory ⓘ
mathematical series ⓘ
appearsInWorkOf G. H. Hardy ⓘ
Hans Rademacher ⓘ
Srinivasa Ramanujan ⓘ
belongsTo q-series in the theory of special functions ⓘ
canEncode Euler totient function ⓘ
Möbius function ⓘ
divisor functions ⓘ
partition function ⓘ
convergesFor |q|<1 in many standard cases ⓘ
field mathematical analysis ⓘ
number theory ⓘ
hasAlternativeDescription power series whose coefficients are Dirichlet convolutions of arithmetic functions ⓘ
hasAnalyticAspect studied via complex analysis of q in the unit disk ⓘ
hasCombinatorialAspect interpreted as weighted counts of divisors ⓘ
hasExample \sum_{n=1}^{\infty} \frac{n q^n}{1-q^n} = \sum_{n=1}^{\infty} \sigma_1(n) q^n ⓘ
\sum_{n=1}^{\infty} \frac{q^n}{1-q^n} = \sum_{n=1}^{\infty} d(n) q^n ⓘ
\sum_{n=1}^{\infty} \mu(n) \frac{q^n}{1-q^n} ⓘ
hasGeneralForm \sum_{n=1}^{\infty} a(n) \frac{q^n}{1-q^n} ⓘ
hasTransformation can be inverted under suitable conditions to recover the underlying arithmetic function ⓘ
introducedBy Johann Heinrich Lambert ⓘ
involves arithmetic functions ⓘ
powers of a variable ⓘ
namedAfter Johann Heinrich Lambert ⓘ
property can be transformed using modular transformations in suitable cases ⓘ
often appear in identities involving divisor sums ⓘ
often express arithmetic functions as coefficients of power series in q ⓘ
relatedConcept Lambert W function (distinct but historically related name) ⓘ
relatedTo Dirichlet series ⓘ
Euler products ⓘ
generating functions ⓘ
mock theta functions ⓘ
modular forms ⓘ
theta functions ⓘ
specialCase q-series ⓘ
typicalConstraintOnCoefficientFunction a(n) is often multiplicative in number-theoretic applications ⓘ
usedFor deriving congruences for partition functions ⓘ
expressing generating functions of divisor-type sequences ⓘ
studying growth of arithmetic functions ⓘ
usedIn combinatorics ⓘ
multiplicative number theory ⓘ
partition theory ⓘ
q-series ⓘ
theory of modular forms ⓘ
variableUsuallyDenotedBy q ⓘ

How these facts were elicited

Referenced by (2)

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

Johann Heinrich Lambert → knownFor → Lambert series ⓘ
Hyperbolic Manifolds and Discrete Groups → topic → Poincaré series ⓘ
linked to: Lambert series