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Problems need HardWork #14

Number Theory Level 2

Find the unit digit of 2^2^2^2^...... (100 times)

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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.

Used and loved by over 6 million people

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including olympiad champions, researchers, and professionals.

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by Dev Sharma

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