#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; typedef long long ll; using ull = unsigned long long; template inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; } //template T gcd(T a, T b) { a = abs(a), b = abs(b); while (b > 0) { tie(a, b) = make_pair(b, a % b); }return a; } //mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count()); constexpr long long INF = 1LL << 60; constexpr int inf = 1000000007; constexpr long long mod = 1000000007LL; //constexpr long long mod = 998244353; struct mint { long long x; mint(long long x = 0) :x((x% mod + mod) % mod) {} mint& operator+=(const mint a) { if ((x += a.x) >= mod) x -= mod; return *this; } mint& operator-=(const mint a) { if ((x += mod - a.x) >= mod) x -= mod; return *this; } mint& operator*=(const mint a) { (x *= a.x) %= mod; return *this; } mint operator+(const mint a) const { mint res(*this); return res += a; } mint operator-(const mint a) const { mint res(*this); return res -= a; } mint operator*(const mint a) const { mint res(*this); return res *= a; } mint pow(ll t) const { if (!t) return 1; mint a = pow(t >> 1); a *= a; if (t & 1) a *= *this; return a; } // for prime mod mint inv() const { return pow(mod - 2); } mint& operator/=(const mint a) { return (*this) *= a.inv(); } mint operator/(const mint a) const { mint res(*this); return res /= a; } }; int main() { std::cin.tie(nullptr); std::ios::sync_with_stdio(false); int n; cin >> n; vector a(n); for (auto& e : a) cin >> e; const int b = (int)sqrt(n); vector sum(b + 1, vector(b + 1)); vector dp(n); dp[0] = 1; for (int i = 0; i < n; i++) { if (i > 0 and a[i - 1] > 1) { dp[i] += dp[i - 1]; } for (int j = 1; j <= b; j++) { dp[i] += sum[j][i % j]; } if (a[i] <= b) { sum[a[i]][i % a[i]] += dp[i]; } else { for (int j = i + a[i]; j < n; j += a[i]) dp[j] += dp[i]; } } cout << dp[n - 1].x << "\n"; }