What row of numbers comes next?
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What row of numbers comes next?
1
11
21
1211
111221
312211
13112221
Show answer & explanation
Answer: A. A) 11321321
Describing the digits of 13112221 gives one 1, one 3, two 1s, three 2s, one 1, generating the next row of the look-and-say sequence.
Step-by-step Derivation:
Step 1: Read consecutive run-lengths in 13112221:
- '1' -> one 1
- '3' -> one 3
- '11' -> two 1s
- '222' -> three 2s
- '1' -> one 1
Step 2: Concatenating yields 11 13 21 32 11 (Option A).