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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 5449 times total.

Classification:
AMS MSC: 00A20 (General :: General and miscellaneous specific topics :: Dictionaries and other general reference works)
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