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General Dirichlet Series

A general Dirichlet series weights complex coefficients by exponential terms indexed by a freely chosen increasing frequency sequence.

Version
v1 · 2026-10-04 · History
Domain-specific #
13733
Domain group
Formal Sciences
Origin domain
Mathematics
Subdomains
Complex Analysis, General Dirichlet Series → Mathematics
Aliases
Generalized Dirichlet series, Lambda-Dirichlet series

Core Idea

A general Dirichlet series is a formal sum \(\sum a_n e^{-\lambda_n s}\), where the coefficients are complex and the real frequency sequence \(\lambda_n\) is nonnegative, strictly increasing, and tends to infinity. The familiar ordinary Dirichlet series uses \(\lambda_n=\log n\). With equally spaced frequencies and \(z=e^{-s}\), the expression instead resembles a power series.[^ref-b0561e034149]

Scope of Application

The form organizes arithmetic Dirichlet series and more general exponential series in complex analysis. With \(a_n=1\) and \(\lambda_n=\log n\), \(\sum n^{-s}\) converges absolutely for \(\Re s>1\) by the \(p\)-series comparison and diverges at real \(s=1\), giving abscissa \(1\). With \(a_n=1\), \(\lambda_n=n\) and \(q=e^{-s}\), the partial sum is \(q(1-q^N)/(1-q)\), yielding \(q/(1-q)\) for \(\Re s>0\); terms fail to vanish for \(\Re s\leq0\), so its abscissa is \(0\). These are worked specializations, not universal thresholds for all coefficients and frequencies.[ref-b0561e034149][ref-4a46b40b4272]

Clarity

State the frequency before transferring a result. Euler products and other arithmetic properties of ordinary \(n^{-s}\) series do not follow from arbitrary frequencies. A formal series need not converge at a finite point; its identity, convergent sum and any later analytic continuation are distinct claims.

Manages Complexity

Separating coefficients from the frequency shows exactly which part changes between an ordinary series and another exponential-series family. It lets the analyst test whether a theorem uses only general frequency conditions or a special arithmetic scale.

Abstract Reasoning

First verify the exponential term form and frequency convention. Then distinguish formal membership from ordinary, absolute or uniform convergence, locate the appropriate abscissa, and check any extra frequency assumptions before applying an analytic result.

Knowledge Transfer

The formal structure transfers across the logarithmic-frequency and equal-step specializations. Convergence and multiplicative conclusions transfer only with their stated hypotheses.

[^ref-b0561e034149]: Ingo Schoolmann, “On Bohr's theorem for general Dirichlet series”, arXiv:1812.04925v2 (2020), Introduction and Section 2. DOI 10.48550/arXiv.1812.04925. [^ref-4a46b40b4272]: Original recurrence-zeta research, Section 3.

Relationships to Other Abstractions

Local relationship map for General Dirichlet SeriesParents appear above the current abstraction, mutual partners to the right, and children below. Node labels state whether each abstraction is prime or domain-specific; colors identify relation types.GeneralDirichlet SeriesDOMAINPrime abstraction: Order — presupposesOrderPRIME

Current abstraction General Dirichlet Series Domain-specific

Parents (1) — more general patterns this builds on

  • General Dirichlet Series presupposes Order Prime

    The defining frequency sequence must be strictly increasing under real-number order.

Hierarchy paths (3) — routes to 3 parentless roots

Neighborhood in Abstraction Space

General Dirichlet Series sits in a sparse region of the domain-specific corpus (96th percentile for distinctiveness): few abstractions share its structure, so a faithful description tends to retrieve it precisely.

Family — Special Functions & Series Convergence (7 abstractions)

Nearest neighbors

Computed from structural-signature embeddings · 2026-10-08