The assignment is to write a program that demonstrates theconcepts used in a
proof that a language L ∉ D using a mapping reduction from H. H= { <M,w> : M
halts on w }, and the proof that H ∉ D is in §19.1. A proof thatanother language L
∉ D using a reduction from H shows that if L ∈ D then H ∈ D. Butwe know that H ∉
D, so by modus tollens L ∉ D.
For example, which we will not do tomorrow, suppose that L≥1 = {<M> : |L(M)| >
0 }, where Σ ≠ Ø. That is, L≥1 consists
OR
OR