#include<bits/stdc++.h>
using namespace std;
#define ll long long int 
vector<ll>ar[200003];
ll dis[200003];
ll mxN=200000;
void seive()
{
    for(int i=1;i<mxN;i++)
    {
        for(int j=i;j<mxN;j+=i)
        {
            ar[j].push_back(i);
        }
    }
}
int main()
{
    ll tc;
    cin>>tc;
    seive();
    while(tc--)
    {
        ll n,k;
        cin>>n>>k;
        vector<ll>v(n),dp(n+1,1e9);
        for(int i=0;i<n;i++)
            cin>>v[i];
        dp[0]=0;
        for(int i=1;i<=mxN;i++)
        {
            dis[i]=1e9;
           
        }
        for(auto it:ar[v[0]])
        {
            dis[it]=min(dis[it],v[0]/it);
        }
        for(int i=1;i<n;i++)
        {
            dp[i]=min(dp[i],dp[i-1]+k);
            for(auto it:ar[v[i]])
            {
                dp[i]=min(dp[i],dis[it]);
            }
            for(auto it:ar[v[i]])
            {
                dis[it]=min(dis[it],dp[i]+(v[i]/it));
            }
        }
        cout<<dp[n-1]<<endl;
    }
    
}