# Tagged Questions

**2**

votes

**1**answer

346 views

### Question on x coordinates of Mordell Curves where $y^2=x^3+k$ and $k^2 = 1$ mod $24$

In my ongoing search for Mordell curves of rank 8 and above I have currently identified 144,499 curves of a type where $k$ is squarefree and $k^2 = 1$ mod $24$.
In each case the x coordinates are ...

**0**

votes

**1**answer

150 views

### Efficiency in deriving differences of divisor pairs

I have a computational problem where I need to derive the differences in divisor pairs in as few cpu cycles as possible.
In particular I am interested in divisors of numbers of the form ...

**5**

votes

**2**answers

503 views

### 12 descent scripts for pari/gp

I'm looking around for scripts to facilitate 12 descent on Mordell curves, preferably in Pari/gp.
I understand that Magma implements this feature, but unfortunately this software isn't available to ...

**18**

votes

**1**answer

554 views

### How to explicitly compute lifting of points from an elliptic curve to a modular curve?

Say $E$ is an elliptic curve over the rationals, of conductor $N$. There's a covering of $E$ by the modular curve $X_0(N)$, and if you rig it right then you can define this map over $\mathbf{Q}$: ...

**2**

votes

**0**answers

414 views

### Tunnell's theorem

Is it possible in some way, to use Tunnells's theorem to determine how long it will take a computer, to determine whether a number n, is a possible area of a rational right triangle?