User blog:KurohaKafka/Turing-incomplete

Restrict Ξ function to S, K, I only or S and I only.

Ξ[I](x)=1 (const)

Ξ[K](x)=x

Ξ[S](x)=?

Ξ[S,I]=?

Ξ[S,I,Ω]=?