#include <bits/stdc++.h>
#define _rep(i, x, y) for(int i = x; i <= y; ++i)
#define _req(i, x, y) for(int i = x; i >= y; --i)
#define _rev(i, u) for(int i = head[u]; i; i = e[i].nxt)
#define pb push_back
#define fi first
#define se second
#define mst(f, i) memset(f, i, sizeof f)
using namespace std;
#ifdef ONLINE_JUDGE
#define debug(...) 0
#else
#define debug(...) fprintf(stderr, __VA_ARGS__), fflush(stderr)
#endif
typedef long long ll;
typedef pair<ll, ll> PII;
namespace fastio{
    #ifdef ONLINE_JUDGE
    char ibuf[1 << 20],*p1 = ibuf, *p2 = ibuf;
    #define get() p1 == p2 && (p2 = (p1 = ibuf) + fread(ibuf, 1, 1 << 20, stdin), p1 == p2) ? EOF : *p1++
    #else
    #define get() getchar()
    #endif
    template<typename T> inline void read(T &t){
        T x = 0, f = 1;
        char c = getchar();
        while(!isdigit(c)){
            if(c == '-') f = -f;
            c = getchar();
        }
        while(isdigit(c)) x = x * 10 + c - '0', c = getchar();
        t = x * f;
    }
    template<typename T, typename ... Args> inline void read(T &t, Args&... args){
        read(t);
        read(args...);
    }
    template<typename T> void write(T t){
        if(t < 0) putchar('-'), t = -t;
        if(t >= 10) write(t / 10);
        putchar(t % 10 + '0');
    }
    template<typename T, typename ... Args> void write(T t, Args... args){
        write(t), putchar(' '), write(args...);
    }
    template<typename T> void writeln(T t){
        write(t);
        puts("");
    }
    template<typename T> void writes(T t){
        write(t), putchar(' ');
    }
    #undef get
};
using namespace fastio;
#define multitest() int T; read(T); _rep(tCase, 1, T)
namespace Calculation{
    const ll mod = 1e9 + 7;
    ll ksm(ll p, ll h){ll base = p % mod, res = 1; while(h){if(h & 1ll) res = res * base % mod; base = base * base % mod, h >>= 1ll;} return res;}
    void dec(ll &x, ll y){x = ((x - y) % mod + mod) % mod;}
    void add(ll &x, ll y){x = (x + y) % mod;}
    void mul(ll &x, ll y){x = x * y % mod;}
    ll sub(ll x, ll y){return ((x - y) % mod + mod) % mod;}
    ll pls(ll x, ll y){return ((x + y) % mod + mod) % mod;}
    ll mult(ll x, ll y){return x * y % mod;}
}
using namespace Calculation;
const int N = 1005;
int n, a[N], nxt[N], nxt2[N], nxt3[N];
ll pw[N];
PII f[N][N], g[N];
void work(PII &x, PII y, PII t){
    add(x.fi, y.fi * t.fi % mod);
    add(x.se, y.fi * t.se % mod + y.se * t.fi % mod);
}
int main(){
    read(n), pw[0] = 1;
    _rep(i, 1, n) pw[i] = pw[i - 1] * 2 % mod;
    _rep(i, 1, n) read(a[i]);
    _rep(i, 1, n) _rep(j, i, n){
        if(a[i] + 20 > a[j]) nxt[i] = j;
        if(a[i] + 75 > a[j]) nxt2[i] = j;
        if(a[i] + 75 >= a[j] + 20) nxt3[i] = j;
    }
    ll ans = 0;
    _rep(i, 1, n){
        PII c = {pw[nxt[i] - i], 2 * pw[nxt[i] - i] % mod};
        f[i][0] = c;
        _rep(j, 1, i - 1) work(f[i][0], g[j], c);
        _rep(j, 1, i - 1){
            if(nxt[j] >= i) continue;
            _rep(k, 0, j - 1){
                if(!k || a[k] + 75 < a[i] + 20){
                    work(f[i][j], f[j][k], c);
                }
            }
            if(nxt3[j] >= nxt[i] + 1){
                int len = nxt3[j] - nxt[i], len2 = nxt2[j] - nxt3[j];
                PII cur = {sub(pw[len], 1) * pw[len2] % mod, 2 * sub(pw[len], 1) * pw[len2] % mod};
                work(g[nxt2[j]], f[i][j], cur);
            }
        }
        add(ans, g[i].se);
        _rep(j, 0, i - 1){
            add(ans, f[i][j].se);
            debug("f(%d,%d):(num:%d,val:%d)\n", i, j, f[i][j].fi, f[i][j].se);
        }
    }
    writeln(ans);
    return 0;
}