Tutorial uses mobius function to solve this problem. How can we solve this using DP, as I have seen many people use it in their solutions.
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Let $$$dp[i]$$$ be the number of ways with $$$\gcd = i$$$.
If you calculate it in descending order of $$$i$$$, $$$dp[i] =$$$ (number of ways with values multiples of $$$i$$$) — $$$\sum_{k=2}^{\lfloor m/i \rfloor} dp[ik]$$$.
You can check out similar techniques in this blog.
Got this bit, thanks! I was looking at your solution 125973986 Just wanted to know if you're storing in kn[i][j] : number of ways after i terms and upto jth multiple of g, or something else?
The former.