In which horizontal row of circles does the number 2018 first appear?
If a number n can be factored as a×b then n will appear in row a+b-1. For example the number 6 appears in row 1+6-1=6 but also row 2+3-1=4.
2018 has only two factorizations, so appears in rows 1+2018-1=2018 and 2+1009-1=1010. The first row it appears in is row 1010.
- Problem by Hana Wehbi
- Solution by Jeremy Galvagni
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