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Hope everyone can give me some suggestions to solve this problem
Difference between en7 and en8, changed 0 character(s)
Given a sequence of integers $( a_1, a_2, \dots, a_n )$ where $( 1 \leq a_i \leq 10^6 )$, count the number of subsequences with indices $( i_1, i_2, \dots, i_k )$ such that:↵

$ k > 0 $,↵

$ 1 < i_2 < \dots < i_k \leq n ,$↵

$ a_{i_1} \leq a_{i_2} \leq \dots \leq a_{i_k} ,$↵

$ \gcd(a_{i_1}, a_{i_2}, \dots, a_{i_k}) = 1 .$↵

The first line contains an integer $n $ $(1 \leq n \leq 3 \times 10^5)$, representing the number of elements in the sequence.↵

The second line contains $ n $ integers $ a_1, a_2, \dots, a_n $ $(1 \leq a_i \leq 10^6)$.↵

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  Rev. Lang. By When Δ Comment
en8 English SpyroK 2024-10-08 15:08:39 0 (published)
en7 English SpyroK 2024-10-08 15:08:04 102
en6 English SpyroK 2024-10-08 15:07:01 393
en5 English SpyroK 2024-10-08 14:58:58 35
en4 English SpyroK 2024-10-08 14:58:43 14
en3 English SpyroK 2024-10-08 14:57:19 9
en2 English SpyroK 2024-10-08 14:56:58 40
en1 English SpyroK 2024-10-08 14:55:57 1086 Bản sửa đổi đầu tiên (saved to drafts)