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2008A Mysterious Sequence
Can you figure out the next number in this sequence?
1, 11, 21, 1211, 111221, ???
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A Mysterious Sequence Solution
The second number is 11 because the the first number consists of 1 one.
The third number is 21 because the second number consists of 2 ones.
The fourth number is 1211 because the third number consists of 1 two and 1 one.
Continuing on like this, the fifth number consists of 3 ones, 2 twos, and 1 one, so the sixth number is:
312211
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