Use the pumping lemma to prove that the following languages are
not regular.
(a)L2 = {y = 10 × x | x and y are binary integers with no
leading 0s, and y is two times x}. (The alphabet for this languages
is {0, 1, ×, =}.) For example, 1010 = 10 × 101 is in L2, but 1010 =
10 × 1 is not.
(b)Let Σ2 = {[ 0 0 ] , [ 0 1 ] , [ 1...
Use the Pumping Lemma to show that the following languages are
not regular.
(a) {ai bj | i > j}
(b) {apaq | for all integers p and q where
q is a prime number and p is not prime}.
Use the pumping lemma to show that the following languages are
not regular.
A a. A1={0^n 1^n 2^n | n≥0}
b. A2 = {www | w ∈ {a,b}∗}
A c. A3 ={a^2^n | n≥0} (Here, a^2^n means a string of 2^n
a’s.)
A ={a3n |n > 0 }
Use the pumping lemma to show that the following languages are
not regular
(c) (5 pts) Let Σ = {0, 1, −, =} and
SUB = {x = y − z | x, y, z are binary integers, and x is the
result of the subtraction of z from y}. For example: 1 = 1 − 0, 10
= 11 − 01 are strings in SUB but not 1 = 1 − 1 or 11 = 11 − 10.
Do not use Pumping Lemma for Regular Expression to prove the
following. You may think of Closure Properties of Regular
Languages
1. Fix an alphabet. For any string w with |w| ≥ 2, let middle(w)
be the string obtained by removing the first and last symbols of w.
That is, Given L, a regular language on Σ, prove that f1(L) is
regular, where
f1(L) = {w : middle(w) ∈ L}