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

template<class T> inline bool chmin(T& a, T b) {
    if(a > b) {
        a = b;
        return true;
    }
    return false;
}

template<class T> inline bool chmax(T& a, T b) {
    if(a < b) {
        a = b;
        return true;
    }
    return false;
}
struct Unionfind {
    vector<int> par;

    Unionfind(int n) : par(n) {
        for(int i = 0; i < n; ++i) par[i] = i;
    }

    int root(int x) {
        if(par[x] == x) return x;
        return par[x] = root(par[x]);
    }

    void unite(int x, int y) {
        int rx = root(x);
        int ry = root(y);
        if(rx == ry) return;
        par[rx] =ry;
    }

    bool same(int x, int y) {
        int rx = root(x);
        int ry = root(y);
        return rx == ry;
    }
};

int main() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);

    int n;
    cin >> n;

    vector<int> a(n+1);
    bool flag1 = true;
    bool equal_i = false;
    int iv = n;
    for(int i = 1; i <= n; ++i) {
        cin >> a[i];
        if(equal_i && a[i] != 0) {
            cout << "No" << endl;
            return 0;
        }
        if(i > 1 && a[i] == i) {
            equal_i = true;
            iv = i;
        }
        if(a[i] > i) flag1 = false;
    }
    if(!flag1) {
        cout << "No" << endl;
        return 0;
    }


    bool flag2 = true;

    for(int i = 1; i <= iv; ++i) {
        if((a[i] + (iv - i)) % i != 0) flag2 = false;
    }

    if(flag2) {
        cout << "Yes" << endl;
        return 0;
    }
    else {
        cout << "No" << endl;
        return 0;
    }
}