#include "bits/stdc++.h"
using namespace std;
#define maxN 1005
#define maxS 50005
int a[maxN];
int prefix[maxS];
int dp[maxN][maxS];
int n;
void helper() {
cin >> n;
for (int i=1; i<=n; i++) cin >> a[i];
for (int i=0; i<=n; i++) fill(dp[i], dp[i]+maxN-1, 0);
for (int i=1; i<=n; i++) prefix[i] = prefix[i-1] + a[i];
for (int r=1; r<=n; r++) {
for (int s=0; s<=maxS-5; s++) {
dp[r][s] = dp[r-1][s];
if (s==a[r]) dp[r][s] = r;
if (s>a[r]) dp[r][s] = max(dp[r][s], dp[r-1][s-a[r]]);
}
}
vector<int> ans;
for (int k=2; k<=n; k++) {
bool ok = 1;
for (int r=k; r<=n; r++) {
int l = r-k+1;
int sum = prefix[r] - prefix[l-1];
if (sum&1) ok = 0;
if (dp[r][sum/2] < l) ok = 0;
}
if (ok) ans.push_back(k);
}
cout << ans.size() << " ";
for (int x: ans) cout << x << " ";
cout << endl;
}
int main() {
int t;
cin >> t;
while (t--) helper();
return 0;
}
