# Seeking help to understand the arguments of Elliptic Curve Expression in SageMath [closed]

Good Day. I'm sorry for my sage code, without formulas, but I looking your help friend.

p = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F
F = FiniteField(p)
E = EllipticCurve(F,[0,7])
print(E[0])


what mean E[0] ????

It very hard to calculate E[0], so, I'm looking for your help friends.

• This is cryptography quescion kalalalaka. Thank you for your answer. Can you help ? Jan 31 at 22:29
• As you see this has nothing to do with cryptography.se. It is all about how the SageMath is working. Feb 1 at 14:19
• Are you after the order $n$ of the group for secp256k1? Yes it's an involved computation, but that's not a secret. PS: It tried to migrate the question to SO, but the system didn't agree, and closed it.
– fgrieu
Feb 1 at 15:31
• And don't cross-post; math Feb 1 at 18:52

E[n] returns the $$n$$-th point in its list of $$F$$-rational points.
Source: __getitem__ in
• Because your curve is too large and it tries to generate the list of $F$-rational points before returning you the first element. Jan 31 at 23:17
• $F$-rational points are just points with coordinates in $F$. Jan 31 at 23:19