Für ein Gitter der Form Γ = Z τ ⊕ Z ⊆ C {\displaystyle {}\Gamma =\mathbb {Z} \tau \oplus \mathbb {Z} \subseteq {\mathbb {C} }} setzt man g 2 ( τ ) = g 2 ( Γ ) {\displaystyle {}g_{2}(\tau )=g_{2}(\Gamma )} , g 3 ( τ ) = g 3 ( Γ ) {\displaystyle {}g_{3}(\tau )=g_{3}(\Gamma )} , Δ ( τ ) = Δ ( Γ ) {\displaystyle {}\Delta (\tau )=\Delta (\Gamma )} und j ( τ ) = j ( Γ ) {\displaystyle {}j(\tau )=j(\Gamma )} .
