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counterexample (Definition)

A counterexample is an example which is used to prove that a statement is false.

For instance, to disprove that the statement ``For all $n$ $2^{2^n} + 1$ is prime.'', one could exhibit $5$ as a counterexample; since $2^{2^5} + 1 = 641 \times 6700417$ the statement is false.




"counterexample" is owned by rspuzio.
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This is version 2 of counterexample, born on 2004-10-09, modified 2005-02-28.
Object id is 6338, canonical name is Counterexample.
Accessed 7764 times total.

Classification:
AMS MSC00A20 (General :: General and miscellaneous specific topics :: Dictionaries and other general reference works)

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