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#include <bits/stdc++.h>
using namespace std;
void File() {
#ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
}
void solve() {
    int n;cin>>n;
    vector<int>a(n);
    for(auto &x:a)cin>>x;
    int lst=a[n-1];
    bool f=1;
    for(int i=n-2;i>=0;i--){
        if(a[i]==lst)
            a[i]=a[i]-2;
        else if(a[i]>lst){
            if((a[i]-lst)%2==0)
                a[i]-=((a[i]-lst-2)+3);
            else
                a[i]-=(a[i]-lst+1);
        }
        lst=a[i];
        if(a[i]<=0){
            f=0;
            break;
        }
    }
    cout<<(f?"YES\n":"NO\n");
}
signed main() {
    File();
    int t = 1;
    cin >> t;
    for (int i = 0; i < t; ++i) {
    //    cout << "Case " << i + 1 << ": ";
        solve();
    }
}
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