Proof pearl: elementary inductive and integer-based proofs about balanced words
نویسندگان
چکیده
Inductive characterizations of words containing the same number of 'a' and 'b' can easily be given. However, formally proving the completeness of some of them turns out to be trickier than one may expect. We discuss and compare two Coq developments relating such balanced words to their inductive characterizations. One is based on auxiliary inductive structures and elementary arguments. The other one is based on a discrete variant of the intermediate value theorem.
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