I saw a post here which I think states that for P256, a is equal to -3.
Why is elliptic curve parameter $a=-3$ somehow special
I am not sure if this is correct, or maybe I am misunderstanding something about elliptic curves?
I thought that a=0 for secp256r1 and some big number for secp256k1?
If we change the value to a=-3, then we no longer have secp256r1 and secp256k1 right?