Change generator in the Stark252PrimeField to one of maximal order $2^{192}$ #572
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Change generator in the Stark252PrimeField to one of maximal order$2^{192}$
Description
We were using a generator of a subgroup of order$2^{48}$ . However, the largest power of 2 that divides p-1, where p is the prime of the Stark252PrimeField, is $2^{192}$ . This PR sets the generator to be $3^{(p-1) / (2^{192})}$ , laying the ground to have domains compatible with the Stone Prover.
Also, since 2^{192} does not fit in a
usize
, this PR slightly changes the way the methodget_primitive_root_of_unity
computes primitives by avoiding a call topow
and manually performing succesive squares of the original root.