It’s universally acknowledged that there’re innumerable trees in the campus of HUST. Given a sequence of numbers a1,a2,…,an, please find the maximum average sequence of a subsequence of those numbers. The definition of average sequence is that the number of pairs that satisfy u divides v or v divides u, divides by the length of the sequence. For example, in the sequence {1,2,3,4}, the maximum average sequence is {1,2,4}. There are three pairs (,,) that satisfy u divides v or v divides u, and the length of the sequence is 3, so the answer is 3÷3=1.
It’s universally acknowledged that there’re innumerable trees in the campus of HUST. Given a sequence of numbers a1,a2,…,an, please find the maximum average sequence of a subsequence of those numbers. The definition of average sequence is that the number of pairs that satisfy u divides v or v divides u, divides by the length of the sequence. For example, in the sequence {1,2,3,4}, the maximum average sequence is {1,2,4}. There are three pairs (<1,2>,<1,4>,<2,4>) that satisfy u divides v or v divides u, and the length of the sequence is 3, so the answer is 3÷3=1.
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