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# DFA, lower bound on number of states, language with primes and remainders

Let $$p \ge 5$$ be a prime number and $$L_p$$ be a language of words over $$\{0,1\}$$ that read in binary from right (i.e. from least significant bit) give a number that gives remainder modulo $$p$$ from the set $$\{1,2, \ldots, \frac{p-1}{2}\}$$.

How to show that:

Every DFA recognizing $$L_p$$ has at least $$2p$$ states.

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