Dirichlet characters and L-functions
Research context
postgraduate concept · established · As of 2026-10-10
A character modulo q is a multiplicative character of the units modulo q extended by zero on integers not coprime to q.
Key knowledge
A character modulo q is a multiplicative character of the units modulo q extended by zero on integers not coprime to q. For Re(s)>1, L(s,chi)=sum chi(n)n^(−s) has an Euler product. Nonprincipal characters have an entire continuation, while the principal character retains the zeta pole multiplied by missing-prime factors. The primitive character's conductor and parity enter its functional equation; an induced character also carries missing-prime Euler factors.
Values and equations
L(s,chi)=sum_n chi(n)n^(−s)=product_p (1−chi(p)p^(−s))^(−1), Re(s)>1
- chi
- Dirichlet character modulo q
- s
- Complex variable
- p
- Prime integer
Conditions and scope
- q is a positive integer and chi's modulus/conductor are recorded distinctly.
- The initial Euler product uses absolute convergence; primitive and induced characters need different factors. Entire continuation and functional-equation scope are separately supported by DLMF §25.15(i), beyond Lecture18's Re(s)>0 continuation.
Sources · 2
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Author checked this English statement, displayed equation where present and stated hypotheses against these source locations: Characters, Euler products and primes in arithmetic progressions; §25.15(i): nonprincipal entire continuation, principal pole, Euler product25.15.2, primitive/induced factors25.15.4 and functional equation25.15.5 including parity. The check is bounded to the recorded claims; no complete proof reconstruction, software proof replay or universal literature completeness is claimed.
2026-10-10 · Author source-body/statement/equation/domain check, with graph associations scoped individually. Separate independent content/source/inventory review is required before branch closure.
Entry details
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