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Odd patterns

Number Theory Level 1

What is the final digit of \(1^1\times3^3\times5^5\times7^7\times\cdots \times2015^{2015}\)?

1 7 5 3 9

Excel in math and science

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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 Rob Matuschek

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