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In a number sequence of 1, 11, 21, 1112, 3112, 211213, why is the next number 312213?

Block
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len walker
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1 Answers1

4

This looks like

A sorted version of the Look-and-Say sequence

In this version

You sort the digits first, then count left to right. So $211213$ sorted is $111223$ which has
$3$ $1$s,
$2$ $2$s and
$1$ $3$ which gives the next number $312213$

hexomino
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