Proposition 4.16. Assuming that:

  • S and ϕ given as in Proposition 4.15

Then there exists n×n matrix M with entries in 𝔽5 and b𝔽5n such that ψ(x)=Mx+b (ψ:𝔽5n𝔽5n^) satisfies ψ(x)=ϕ(x) for Ωδ(|𝔽5n|) elements xS.