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Composite or Prime

Number Theory Level 1

If n is a composite number, then 2^{n} - 1 is which of them?

Composite Prime

Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

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Our wiki is made for math and science

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including olympiad champions, researchers, and professionals.

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by Saunak Bhattacharjee

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