// https://www.youtube.com/watch?v=CrymicX875M
// Angel of mercy
// How did you move me
// Why am I on my feet again

#ifndef ONLINE_JUDGE
#include "templates/debug.hpp"
#else
#define debug(...)
#endif

#include <bits/stdc++.h>
using namespace std;
using i64 = int64_t;
using u64 = uint64_t;


namespace modint {

using i64 = int64_t;

template <int P>
struct Mint {
   private:
    constexpr Mint power(Mint x, i64 p) const {
        Mint res = 1;
        while (p > 0) {
            if (p & 1) {
                res *= x;
            }
            x *= x;
            p >>= 1;
        }
        return res;
    }

    constexpr int norm(int x) const {
        if (x < 0) {
            x += getMod();
        }
        if (x >= getMod()) {
            x -= getMod();
        }
        return x;
    }

   public:
    int x;
    constexpr Mint() : x{} {}
    constexpr Mint(i64 x) : x{norm(x % getMod())} {}
    static int mod;
    constexpr static int getMod() {
        if (P > 0) {
            return P;
        } else {
            return mod;
        }
    }
    constexpr static void setMod(int Mod_) { mod = Mod_; }

    constexpr int val() const { return x; }
    explicit constexpr operator int() const { return x; }
    constexpr Mint operator-() const {
        Mint res;
        res.x = norm(getMod() - x);
        return res;
    }
    constexpr Mint inv() const {
        assert(x != 0);
        return power(*this, getMod() - 2);
    }
    constexpr Mint pow(i64 r) const { return power(*this, r); }
    constexpr Mint &operator*=(Mint rhs) & {
        x = 1LL * x * rhs.x % getMod();
        return *this;
    }
    constexpr Mint &operator+=(Mint rhs) & {
        x = norm(x + rhs.x);
        return *this;
    }
    constexpr Mint &operator-=(Mint rhs) & {
        x = norm(x - rhs.x);
        return *this;
    }
    constexpr Mint &operator/=(Mint rhs) & { return *this *= rhs.inv(); }
    friend constexpr Mint operator*(Mint lhs, Mint rhs) {
        Mint res = lhs;
        res *= rhs;
        return res;
    }
    friend constexpr Mint operator+(Mint lhs, Mint rhs) {
        Mint res = lhs;
        res += rhs;
        return res;
    }
    friend constexpr Mint operator-(Mint lhs, Mint rhs) {
        Mint res = lhs;
        res -= rhs;
        return res;
    }
    friend constexpr Mint operator/(Mint lhs, Mint rhs) {
        Mint res = lhs;
        res /= rhs;
        return res;
    }
    friend constexpr std::istream &operator>>(std::istream &is, Mint &a) {
        i64 v;
        is >> v;
        a = Mint(v);
        return is;
    }
    friend constexpr std::ostream &operator<<(std::ostream &os, const Mint &a) {
        return os << a.val();
    }
    friend constexpr bool operator==(Mint lhs, Mint rhs) {
        return lhs.val() == rhs.val();
    }
    friend constexpr bool operator!=(Mint lhs, Mint rhs) {
        return lhs.val() != rhs.val();
    }
};

template <int P>
int Mint<P>::mod{0};

template <typename Z>
struct Comb {
    std::vector<Z> fact, inv_fact;
    Comb(int n) {
        fact.resize(n + 1, Z(1));
        inv_fact.resize(n + 1, Z(1));
        for (int i = 1; i <= n; i++) {
            fact[i] = fact[i - 1] * i;
        }
        inv_fact[n] = Z{1} / fact[n];
        for (int i = n - 1; i >= 0; i--) {
            inv_fact[i] = inv_fact[i + 1] * (i + 1);
        }
    }
    Z get(int n, int m) const {
        if (n < m || m < 0) return 0;
        return fact[n] * inv_fact[m] * inv_fact[n - m];
    }
};
}  // namespace modint

// check the modulus!!!
constexpr int MOD = 1e9 + 7;

using Z = modint::Mint<MOD>;
using C = modint::Comb<Z>;

constexpr int L = 76;
array<array<array<Z, L>, L>, L> dp, ndp;

// #define int i64
void solve() {
    int n; cin >> n;
    Z ans = 0;
    vector<Z> pw2(n + 1);
    pw2[0] = 1;
    for (int i = 1; i <= n; i++) {
        pw2[i] = pw2[i - 1] * 2;
    }
    dp[0][0][0] = 1;
    int last = 0;
    for (int i = 0; i < n; i++) {
        array<array<array<Z, L>, L>, L> ndp;
        int t; cin >> t;
        int d = t - last;
        for (int x = -1; x + 1 < L; x++) {
            for (int y = -1; y + 1 < L; y++) {
                for (int z = -1; z + 1 < L; z++) {
                    if (dp[x + 1][y + 1][z + 1] == 0) continue;
                    array<int, 6> f; f.fill(-1);
                    f[0] = max(f[0], x - d), f[1] = max(f[1], y - d), f[2] = max(f[2], z - d);
                    for (int t = 1; t < 6; t++) {
                        f[t] = max(f[t], f[t - 1] + 20);
                        if (t >= 3) f[t] = max(f[t], f[t - 3] + 75);
                    }
                    ndp[f[0] + 1][f[1] + 1][f[2] + 1] += dp[x + 1][y + 1][z + 1];
                    int j = 0; while (f[j] < 0) j++;
                    ans += dp[x + 1][y + 1][z + 1] * j * pw2[n - i - 1];
                    ndp[f[j] + 1][f[j + 1] + 1][f[j + 2] + 1] += dp[x + 1][y + 1][z + 1];
                }
            }
        }
        last = t;
        dp.swap(ndp);
    }
    cout << ans * 2 << '\n';
}
#undef int

// Make bold hypotheses and verify carefully
int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    };
}