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(b|ab)*(a|ε)(b|ab)*(a|ε) — no two consecutive a'sCombinedFormal RE✨ Emoji Combos

Strings over {a,b} with no two adjacent a's. Every a must be followed by b (or end the string). 3-state minimal DFA.

✓ Accepts
εababbabababa
✗ Rejects
aaaabbaabaab
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