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Each of the sets F_0, F_1,
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02 Mar 2025, 13:03
\(F_7\) contains 7, 17, 27, etc.
The cube of 7 = 7 * 7 * 7 = 343
You could actually stop here, save time, and determine that the set must be \(F_3\), since 343 ends in 3.
No other set aside from \(F_3\) would contain the integer 343 since all of the integers in all of the other sets end with a digit other than 3.
Just to further prove the point though:
The cube of 17 = 17 * 17 * 17 = 4913
The cube of 27 = 27 * 27 * 27 = 19683
Again, the cubes end in the digit 3, so they are contained in \(F_3\)