No me simpatizas...

Extraido de Arithmetic of Elliptic Curves --- Silverman:

"The calculation of an equation for the twist E_D is straightforward. The case j(E) != 0, 1728 was already done in (2.4). We will do j(E) = 1728 here, and leave j(E) = 0 for the reader."

... Ou! realmente ocupamos ese caso :'(

En fin, se supone que podemos obtenerla facilmente.