// Online C++ compiler to run C++ program online
#include <bits/stdc++.h>
using namespace std;
int main() {
int t;
cin>>t;
while(t--)
{
long int n,m,c=0;
cin>>n;
int a[n];
for(int i=0;i<n;i++)
{
cin>>m;
a[i]=m;
}
for(int j=n-1;j>=0;j--)
{
for(int i=j-1;i>=0;i--)
{
if((a[j]-a[i])==(j-i))
c++;
}
}
cout<<c<<endl;
}
return 0;
}
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