Eisenstein–Kronecker number

In mathematics, Eisenstein–Kronecker numbers are an analogue for imaginary quadratic fields of generalized Bernoulli numbers.

[1][2][3] They are defined in terms of classical Eisenstein–Kronecker series, which were studied by Kenichi Bannai and Shinichi Kobayashi using the Poincaré bundle.

[3][4] Eisenstein–Kronecker numbers are algebraic and satisfy congruences that can be used in the construction of two-variable p-adic L-functions.

[3][5] They are related to critical L-values of Hecke characters.

[1][5] When A is the area of the fundamental domain of

divided by

π

{\displaystyle \Gamma }

is a lattice in

(

γ ∈

γ ¯

+ γ

⟨ γ ,

is the complex conjugate of z.