#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); ++i)
using namespace std;
using ll = long long;

int main() {
    ll N;
    cin >> N;
    vector<ll> A(N);
    rep(i, N) {
        cin >> A[i];
        if (i + 1 < A[i]) {
            cout << "No" << endl;
            return 0;
        }
    }

    vector<ll> revSum(N + 1, 0);

    for (int i = N - 1; i >= 0; --i) {
        revSum[i] = revSum[i + 1] + A[i];
    }

    for (int i = 0; i < N; i++) {
        if (revSum[i] % (i + 1) != 0) {
            cout << "No" << endl;
            return 0;
        }
    }
    cout << "Yes" << endl;

    return 0;
}