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using namespace std;
#define forl(i, l, r) for (int i = l; i <= r; i++)
#define forr(i, r, l) for (int i = r; i >= l; i--)
#define for1(i, n) for (int i = 1; i <= n; i++)
#define fro1(i, n) for (int i = 1; i <= n; i++)
#define for0(i, n) for (int i = 0; i < n; i++)
#define fro0(i, n) for (int i = 0; i < n; i++)
#define meminf(a) memset(a, inf, sizeof(a))
#define mem_1(a) memset(a, -1, sizeof(a))
#define mem0(a) memset(a, 0, sizeof(a))
#define memcp(a,b) memcpy(a,b,sizeof(b))
#define oper(type) bool operator <(const type y)const
#define mp make_pair
#define pu_b push_back
#define pu_f push_front
#define po_b pop_back
#define po_f pop_front
#define fi first
#define se second
#define whiel while
#define retrun return
typedef pair<long long, long long> pll;
typedef vector<long long> vll;
typedef pair<int, int> pii;
typedef unsigned long long ull;
typedef vector<int> vii;
typedef double db;
typedef long long ll;
typedef int itn;
void (initializer_list<int*> li){for(auto ptr=li.begin();ptr!=li.end();ptr++)scanf("%d",*ptr);}
void (initializer_list<ll*> li){for(auto ptr=li.begin();ptr!=li.end();ptr++)scanf("%lld",*ptr);}
void (initializer_list<db*> li){for(auto ptr=li.begin();ptr!=li.end();ptr++)scanf("%lf",*ptr);}
void out(initializer_list<int> li){for(auto ptr=li.begin();ptr!=li.end();ptr++)printf("%d ",*ptr);}
void outln(initializer_list<int> li){for(auto ptr=li.begin();ptr!=li.end();ptr++)printf("%dn",*ptr);}
void out(initializer_list<ll> li){for(auto ptr=li.begin();ptr!=li.end();ptr++)printf("%lld ",*ptr);}
void outln(initializer_list<ll> li){for(auto ptr=li.begin();ptr!=li.end();ptr++)printf("%lldn",*ptr);}
int (int &a,int &b,int &c,int &d){return scanf("%d%d%d%d",&a,&b,&c,&d);}
int (int &a,int &b,int &c){return scanf("%d%d%d",&a,&b,&c);}
int in(int &a,int &b){return scanf("%d%d",&a,&b);}
int in(ll &a){return scanf("%lld",&a);}
int in(int &a){return scanf("%d",&a);}
int in(char *s){return scanf("%s",s);}
int in(char &c){return scanf("%c",&c);}
void out(int a,bool ln){printf("%d%c",a,ln? 'n':' ');}
void out(ll a,bool ln){printf("%lld%c",a,ln? 'n':' ');}
void out(db a,int digit,bool ln){printf("%.*f%c",digit,a,ln? 'n':' ');}
const db pi = acos((db)-1);
const ll inf =0x3f3f3f3f;
const db eps = 1e-8;
const int N = 1.1e3;
const int M = 2.1e5;
const ll mod = 1e9+7;
int sign(db a) {return a < -eps ? -1 : a > eps;}
int db_cmp(db a, db b){ return sign(a-b);}
int a[N];
ll qPow(ll a, ll b, ll c) {
ll ret = 1;
while (b) {
if (b & 0x1) ret = ret * a % c;
a = a * a % c;
b >>= 1;
}
return ret;
}
int main() {
#ifdef PerpEternal
freopen("/Users/perpeternal/Documents/Sketch/data/in.dat", "r", stdin);
#endif
int n;
while(~in(n)){
for1(i,n)in(a[i]);
ll ans=0;
for1(i,n){
ll tm=1;
for1(j,n){
if(j!=i){
tm=tm*((1ll*a[j]*a[j]%mod-1ll*a[i]*a[i]%mod+mod)%mod)%mod;
}
}
ans=(ans+qPow(2*a[i],mod-2,mod)*qPow(tm,mod-2,mod)%mod)%mod;
}
out(ans,1);
}
return 0;
}
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