#include <bits/stdc++.h>
#define ll long long
#define ull unsigned ll
constexpr auto PI = 3.141592653589793238462643383279502884;
const ll MM = 1e9 + 7, N = 2e3 + 10;
const ll MAX = 2e18;
using namespace std;
ll gcd(ll a, ll b) {
if (a < b)swap(a, b);
if (b == 0)return a;
return gcd(b, a % b);
}
ll lcm(ll a, ll b) {
return a * b / gcd(a, b);
}
ll numberOfDiviser(ll a) {
if (a == 1)return 0;
ll ans = 1;
ll i;
for (i = 2; i * i < a; i++) {
if (a % i == 0)ans += 2;
}
if (i * i == a)ans++;
return ans;
}
ll pow(ll a, ll b, ll m) {
if (b == 0)return 1;
if (b == 1)return a;
ll x = pow(a, b / 2, m);
x = (x * x) % m;
if (b % 2)x = (x * a);
return x % m;
}
ll inverse_mod(ll a, ll m) {
return pow(a, m - 2, m);
}
int n;
ll dp[N][N][8];
ll DP(int i=0, int j=0, int last=0) {
if (i == n)return (j==0&&last==5);
if (dp[i][j][last] + 1)return dp[i][j][last];
ll res = 0;
int last1;
if (last < 3)last1 = last + 1;
else if (last == 3 || last == 5)last1 = last;
else last1 = 1;
res += DP(i + 1, j + 1, last1);
if (last < 3)last1 = 0;
else if (last < 5)last1 = last + 1;
else last1 = 5;
if(j)
res += DP(i + 1, j - 1, last1);
return dp[i][j][last] = res%MM;
}
int solve() {
cin >> n;
memset(dp, -1, sizeof(dp));
cout << DP();
return 0;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
std::cout.tie(0);
int t = 1;//cin >> t;
int i = 1;
while (t--) {
//cout << "Case #" << i++ << ": ";
solve();
}
}
/*
*/
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