#include <iostream>
#include <cstring>
#include <cstdio>

using namespace std;

typedef long long ll;
const int MOD = 1e9+7;

int n;
int A[1501];

int DP[1501][1501];

int fac[1501], rev[1501], rfac[1501];

void set()
{
    fac[0] = 1;
    for (int i = 1; i < 1501; i++)
        fac[i] = (ll)i*fac[i-1]%MOD;

    rev[1] = 1;
    for (int i = 2; i < 1501; i++)
        rev[i] = (ll)rev[MOD%i]*(MOD-MOD/i)%MOD;

    rfac[0] = 1;
    for (int i = 1; i < 1501; i++)
        rfac[i] = (ll)rfac[i-1]*rev[i]%MOD;
}

int ask(int O, int P)
{
    if ( DP[O][P] == -1 ) {
        DP[O][P] = 0;

        if ( O+P > n+1 ) return DP[O][P];

        int p = 0;

        for (int i = O; i < O+P; i++) {
            if ( A[i] < p ) return DP[O][P];
            p = A[i];
        }

        if ( O+P == n+1 ) return DP[O][P] = 1;

        for (int Pi = 1; Pi <= P; Pi++)
            DP[O][P] += (ll)ask(O+P, Pi)*fac[P]%MOD*rfac[P-Pi]%MOD, DP[O][P] %= MOD;
    }

    return DP[O][P];
}

int main()
{
    set();
    memset(DP, -1, sizeof(DP));

    scanf("%d", &n);

    for (int ni = 1; ni <= n; ni++)
        scanf("%d", &A[ni]);

    int ans = 0;

    for (int ni = 1; ni <= n; ni++)
        ans += ask(1, ni), ans %= MOD;

    printf("%d\n", ans);
}