A sequence of numbers follows a strict logical rule: 1, 11, 21, 1211, 111221. What is the next number in the sequence?
312211
This is the Look-and-Say sequence, where each number describes the digits of the previous one. Reading '111221' out loud gives 'three 1s, two 2s, one 1', which becomes 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: Hard. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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