#include <iostream>
#include <vector>
using namespace std;
const int smax = 5e4;
const int nmax = 1e3;
int p[smax + 1];
int s[nmax + 1];
vector < int > sol[2];
void solve () {
sol[0].clear ();
sol[1].clear ();
s[0] = p[0] = 0;
for ( int i = 1; i <= smax; i++ )
p[i] = -1;
int n, x;
cin >> n;
for ( int i = 1; i <= n; i++ ) {
cin >> x;
s[i] = s[i - 1] + x;
for ( int j = min ( s[i], smax ) - x; j >= 0; j-- )
p[j + x] = max ( p[j + x], p[j] );
if ( x <= smax )
p[x] = i;
sol[i % 2].clear ();
sol[1 - i % 2].push_back ( i );
int sum;
for ( auto x: sol[1 - i % 2] )
if ( ( sum = ( s[i] - s[i - x] ) ) % 2 == 0 && p[sum / 2] >= i - x + 1 )
sol[i % 2].push_back ( x );
}
cout << sol[n % 2].size () << ' ';
for ( auto x: sol[n % 2] )
cout << x << ' ';
cout << '\n';
}
int main() {
int t;
cin >> t;
while ( t-- )
solve ();
return 0;
}
