#include<bits/stdc++.h>
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define SZ(x) ((int)x.size())
#define ALL(x) x.begin(),x.end()
#define L(i,u) for (register int i=head[u]; i; i=nxt[i])
#define rep(i,a,b) for (register int i=(a); i<=(b); i++)
#define per(i,a,b) for (register int i=(a); i>=(b); i--)
using namespace std;
typedef long double ld;
typedef long long ll;
typedef unsigned int ui;
typedef pair<int,int> Pii;
typedef pair<ll,ll> Pll;
typedef vector<int> Vi;
template<class T> inline void read(T &x){
    x=0; char c=getchar(); int f=1;
    while (!isdigit(c)) {if (c=='-') f=-1; c=getchar();}
    while (isdigit(c)) {x=x*10+c-'0'; c=getchar();} x*=f;
}
template<class T> T gcd(T a, T b){return !b?a:gcd(b,a%b);}
template<class T> inline void umin(T &x, T y){x=x<y?x:y;}
template<class T> inline void umax(T &x, T y){x=x>y?x:y;}
mt19937 R(chrono::system_clock().now().time_since_epoch().count());

const int N = 1<<18|3, mo = 1e9+7, inv2 =(mo+1)/2;
const ll MOD=7LL*mo*mo;
inline void add(int &x, int y){x=x+y<mo?x+y:x+y-mo;}
inline void sub(int &x, int y){x=x-y>=0?x-y:x-y+mo;}
inline int power(int a, int n) {
    int res=1;
    while (n) {
        if (n&1) res=1LL*res*a%mo;
        a=1LL*a*a%mo; n>>=1;
    }
    return res;
}
int n,a[N];
int main() {
    int t;read(t);while(t--){
        read(n);rep(i,1,n)read(a[i]),a[i]>>=1;
        int res=a[1];
        rep(i,2,n)res=(res+1ll*a[i]*(a[i]-a[i-1])%mo*power(2*a[i],mo-2))%mo;
        cout<<res<<endl;
    }
    return 0;
}