Arithmetic of the modular function $j_{1,4}$
Arithmetic of the modular function $j_{1,4}$
We find a generator $j_{1,4}$ of the function field on the modular curve X₁(4) by means of classical theta functions θ₂ and θ₃, and estimate the normalized generator $N(j_{1,4})$ which becomes the Thompson series of type 4C. With these modular functions w