#include <bits/stdc++.h>
using namespace std;

#define ms(s, n) memset(s, n, sizeof(s))
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define FORd(i, a, b) for (int i = (a) - 1; i >= (b); i--)
#define FORall(it, a) for (__typeof((a).begin()) it = (a).begin(); it != (a).end(); it++)
#define FORalld(it, a) for (__typeof((a).rbegin()) it = (a).rbegin(); it != (a).rend(); it++)
#define sz(a) int((a).size())
#define present(t, x) (t.find(x) != t.end())
#define all(a) (a).begin(), (a).end()
#define uni(a) (a).erase(unique(all(a)), (a).end())
#define pb push_back
#define pf push_front
#define mp make_pair
#define fi first
#define se second
#define prec(n) fixed<<setprecision(n)
#define bit(n, i) (((n) >> (i)) & 1)
#define bitcount(n) __builtin_popcountll(n)
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pi;
typedef vector<int> vi;
typedef vector<pi> vii;
const int MOD = (int) 1e9 + 7;
const int INF = (int) 1e9;
const ll LINF = (ll) 1e18;
const ld PI = acos((ld) -1);
const ld EPS = 1e-9;
inline ll gcd(ll a, ll b) {ll r; while (b) {r = a % b; a = b; b = r;} return a;}
inline ll lcm(ll a, ll b) {return a / gcd(a, b) * b;}
inline ll fpow(ll n, ll k, int p = MOD) {ll r = 1; for (; k; k >>= 1) {if (k & 1) r = r * n % p; n = n * n % p;} return r;}
template<class T> inline int chkmin(T& a, const T& val) {return val < a ? a = val, 1 : 0;}
template<class T> inline int chkmax(T& a, const T& val) {return a < val ? a = val, 1 : 0;}
template<class T> inline T isqrt(T k) {T r = sqrt(k) + 1; while (r * r > k) r--; return r;}
template<class T> inline T icbrt(T k) {T r = cbrt(k) + 1; while (r * r * r > k) r--; return r;}
inline void addmod(int& a, int val, int p = MOD) {if ((a = (a + val)) >= p) a -= p;}
inline void submod(int& a, int val, int p = MOD) {if ((a = (a - val)) < 0) a += p;}
inline int mult(int a, int b, int p = MOD) {return (ll) a * b % p;}
inline int inv(int a, int p = MOD) {return fpow(a, p - 2, p);}
inline int sign(ld x) {return x < -EPS ? -1 : x > +EPS;}
inline int sign(ld x, ld y) {return sign(x - y);}

template<class T, class mul, class dvd, class mod> struct FiniteField {
    T x;
    template<class G> T normalize(G x) {
        T p = mod().get();
        if (x >= 0 && x < p) return x;
        x %= p;
        if (x < 0) x += p;
        else if (x >= p) x -= p;
        return x;
    }
    FiniteField() : x(0) {}
    template<class G> FiniteField(const G& y) {
        x = normalize(y);
    }
    FiniteField(const FiniteField& rhs) : x(rhs.x) {
    }
    template<class G> FiniteField operator = (const G& y) {
        x = normalize(y);
        return *this;
    }
    int operator == (const FiniteField& rhs) const {
        return x == rhs.x;
    }
    int operator != (const FiniteField& rhs) const {
        return x != rhs.x;
    }
    int operator < (const FiniteField& rhs) const {
        return x < rhs.x;
    }
    FiniteField operator ++(int) {
        T p = mod().get();
        FiniteField res = *this;
        if ((++x) >= p) x -= p;
        return res;
    }
    FiniteField operator ++() {
        T p = mod().get();
        if ((++x) >= p) x -= p;
        return *this;
    }
    FiniteField operator --(int) {
        T p = mod().get();
        FiniteField res = *this;
        if ((--x) < 0) x += p;
        return res;
    }
    FiniteField operator --() {
        T p = mod().get();
        if ((--x) < 0) x += p;
        return *this;
    }
    template<class G> FiniteField operator += (const G& y) {
        T p = mod().get();
        if ((x += normalize(y)) >= p) x -= p;
        return *this;
    }
    template<class G> FiniteField operator -= (const G& y) {
        T p = mod().get();
        if ((x -= normalize(y)) < 0) x += p;
        return *this;
    }
    FiniteField operator += (const FiniteField& rhs) {
        T p = mod().get();
        if ((x += rhs.x) >= p) x -= p;
        return *this;
    }
    FiniteField operator -= (const FiniteField& rhs) {
        T p = mod().get();
        if ((x -= rhs.x) < 0) x += p;
        return *this;
    }
    FiniteField operator + (const FiniteField& rhs) const {
        T p = mod().get();
        FiniteField res;
        res.x = x + rhs.x;
        if (res.x >= p) res.x -= p;
        return res;
    }
    FiniteField operator - (const FiniteField& rhs) const {
        T p = mod().get();
        FiniteField res;
        res.x = x - rhs.x;
        if (res.x < 0) res.x += p;
        return res;
    }
    template<class G> FiniteField operator *= (const G& y) {
        T p = mod().get();
        x = mul()(x, normalize(y), p);
        return *this;
    }
    template<class G> FiniteField operator /= (const G& y) {
        T p = mod().get();
        x = dvd()(x, normalize(y), p);
        return *this;
    }
    FiniteField operator *= (const FiniteField& rhs) {
        T p = mod().get();
        x = mul()(x, rhs.x, p);
        return *this;
    }
    FiniteField operator /= (const FiniteField& rhs) {
        T p = mod().get();
        x = dvd()(x, rhs.x, p);
        return *this;
    }
    template<class G> FiniteField operator * (const G& y) const {
        T p = mod().get();
        FiniteField res;
        res.x = mul()(x, res.normalize(y), p);
        return res;
    }
    template<class G> FiniteField operator / (const G& y) const {
        T p = mod().get();
        FiniteField res;
        res.x = dvd()(x, res.normalize(y), p);
        return res;
    }
    FiniteField operator * (const FiniteField& rhs) const {
        T p = mod().get();
        FiniteField res;
        res.x = mul()(x, rhs.x, p);
        return res;
    }
    FiniteField operator / (const FiniteField& rhs) const {
        T p = mod().get();
        FiniteField res;
        res.x = dvd()(x, rhs.x, p);
        return res;
    }
    template<class G> friend FiniteField operator * (const G& y, const FiniteField& rhs) {
        FiniteField res;
        res.x = res.normalize(y);
        return res * rhs;
    }
    template<class G> friend FiniteField operator / (const G& y, const FiniteField& rhs) {
        FiniteField res;
        res.x = res.normalize(y);
        return res / rhs;
    }
    template<class G> FiniteField operator ^= (G k) {
        T p = mod().get();
        if (k == 0) {
            x = 1;
            return *this;
        }
        T t = x; k--;
        while (k > 0) {
            if (k & 1) x = mul()(x, t, p);
            t = mul()(t, t, p);
            k >>= 1;
        }
        return *this;
    }
    template<class G> FiniteField operator ^ (G k) const {
        T p = mod().get();
        if (k == 0) return 1;
        T r = x, t = x; k--;
        while (k > 0) {
            if (k & 1) r = mul()(r, t, p);
            t = mul()(t, t, p);
            k >>= 1;
        }
        return r;
    }
    friend istream& operator >> (istream& is, FiniteField& rhs) {
        is >> rhs.x;
        rhs.x = rhs.normalize(rhs.x);
        return is;
    }
    friend ostream& operator << (ostream& os, const FiniteField& rhs) {
        os << rhs.x;
        return os;
    }
};
template<class T> class mul {
public:
    T operator () (const T& x, const T& y, const T& p) {
        return (long long) x * y % p;
    }
};
template<class T> class dvd {
public:
    T operator () (const T& x, const T& y, const T& p) {
        pair<T, T> r = euclid(y, p);
        return mul<T>()(x, (r.first % p + p) % p, p);
    }
private:
    pair<T, T> euclid(T a, T b) {
        if (b == 0) return make_pair(1, 0);
        pair<T, T> r = euclid(b, a % b);
        return make_pair(r.second, r.first - a / b * r.second);
    }
};
template<class T> class mod {
public:
    T get() {
        return (T) 1e9 + 7;
    }
};
typedef FiniteField<int, mul<int>, dvd<int>, mod<int> > FF;

const int maxn = 1200 + 5;
int n;
int a[maxn];
int f[maxn][maxn];
FF fac[maxn];
FF ifac[maxn];
FF dp[maxn][maxn];

FF calc(int pos, int d) {
    if (pos == n) return 1;
    FF& res = dp[pos][d];
    if (res != -1) return res;
    res = 0;
    FOR(k, 1, d + 1) if (f[pos][pos + k - 1]) {
        res += calc(pos + k, k) * ifac[d - k];
    }
    res *= fac[d];
    return res;
}

void solve() {
    fac[0] = 1; FOR(i, 1, maxn) fac[i] = fac[i - 1] * i;
    FOR(i, 0, maxn) ifac[i] = 1 / fac[i];
    FOR(i, 0, maxn) FOR(j, 0, maxn) dp[i][j] = -1;
    cin >> n;
    FOR(i, 0, n) cin >> a[i], a[i]--;
    FOR(i, 0, n) {
        f[i][i] = 1;
        FOR(j, i + 1, n) {
            if (a[j] < a[j - 1]) break;
            f[i][j] = 1;
        }
    }
    FF res = 0;
    FOR(i, 1, n + 1) {
        if (f[0][i - 1]) {
            res += calc(i, i);
        }
    }
    cout << res << "\n";
}

int main() {
#ifdef _LOCAL_
    freopen("in.txt", "r", stdin); //freopen("out.txt", "w", stdout);
#else
    ios_base::sync_with_stdio(0); cin.tie(0);
#endif
    solve();
    cerr << "\nTime elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << "s\n";
    return 0;
}