Consider the following sequence of numbers: 1, 11, 21, 1211, 111221, ... What is the next term in the sequence?
312211
This is the 'Look-and-Say' sequence. Each term describes the digits of the previous term. '111221' consists of three 1s, two 2s, and one 1, which translates to '312211'.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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