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A Sequence

Level pending

What the next term in the sequence following sequence?

1, 11, 21, 1211, 111221, 312211, 13112221, 1113213211...

12233121312123 1231231213212112 123211321313312 31131211131221

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.

Used and loved by 4 million people

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.

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by Victor Paes Plinio

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