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A problem by brittany gutknecht

Level pending

A grid with 3 rows and 52 columns is tiled with 78 identical 2 x 1 dominoes. How many ways can this be done in such a way that two dominoes are vertical?

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, conceptual quizzes.

Our wiki is made for math and science

Master advanced concepts through explanations,
examples, and problems from the community.

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including olympiad champions, researchers, and professionals.

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