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Inspired by Gavin Lo

Number Theory Level 2

\[ \Large 9 ^ { 9 ^ 9 } \]

What are the last 2 digits of the above number?

01 81 09 89

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Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, interactive explorations.

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including olympiad champions, researchers, and professionals.

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by Calvin Lin

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