Prove that

L = {0^x 1^y 2^x+y | x >= 0 and y >=1} is not Regular.

Must use Closure(s).

[ Describe the language in English first ]

Hint: Your "destination" should be

{ a^z b^z | z >= 1} = a language with as followed by the same number of bs, which we know is not Regular.

Start with L

(show a sequence of operations and results)

1. Describe Operation Result

End with {a^z b^z} which is not regular

2. Conclusion about L: